diff --git a/basics.py b/basics.py
new file mode 100644
index 0000000..2e8f7d6
--- /dev/null
+++ b/basics.py
@@ -0,0 +1,213 @@
+# print("Hello Basics From python")
+# print("asif",24,sep='-',end='\n')
+# print("Hello","World",24,True,end='',sep='')
+
+#single line comment
+"""High
+This is a 
+multi line
+comment"""
+import sys
+#data types - numeric(int,float,boolean,complex)
+# int_var = 24433432849486984
+# print(int_var,type(int_var))
+# print(sys.getsizeof(int_var))
+
+# float_var = 12342242242242.24225223243224424
+# print(float_var,type(float_var))
+# print(sys.getsizeof(float_var))
+
+# bool1 = True
+# bool2 = False
+
+# print(bool1,type(bool1))
+# print(sys.getsizeof(bool1))
+# print(bool2,type(bool2))
+# print(sys.getsizeof(bool2))
+
+# complex1 = 2 + 3j
+# complex2 = complex(2,3)
+# print(complex1,type(complex1))
+# print(sys.getsizeof(complex1))
+
+#sequence typed - string,list,tuple
+# str1 = "Hello Asif"
+# print(str1,type(str1))
+# str2 = str(23)
+# print(str2,type(str2))
+# print("\n")
+# l1 = [12,3,342,42]
+# t1 = (12,32,1132,23)
+# print(l1,type(l1))
+# print(t1,type(t1))
+
+# s = {12,3,22,324,2}
+# print(s,type(s))
+
+# dict1 = {"name":"Asif","age":24}
+# print(dict1,type(dict1))
+
+# a = None
+# print(a,type(a))
+
+# a = 23
+# print(a)
+# a = "Asif"
+# print(a)
+# a = True
+# print(a)
+
+# a,b,c = 23,34,22
+# print(a,b,c)
+
+# #keywords - for,if,else
+
+# a = b = c = 100
+# print(a,b,c)
+# print(id(a),id(b),id(c))
+
+# name = input("What's your name:")
+# print("Your name is:",name)
+
+#type conversion
+# var1 = int(123)
+# # var2 = int("Asif")
+# var2 = int(12.232)
+# print(var1,var2)
+
+# var3 = float(23)
+# print(var3)
+
+# print("23"+23)
+
+# print("Data","Science","Mentorship","Progran","By","CampusX",sep='-',end="\n")
+
+# celcius = float(input("Enter celcius value:"))
+# farenheit = (9 * celcius)/5 + 32
+# print("In farenheit:",farenheit)
+
+# num1 = int(input("enter a number:"))
+# num2 = int(input("enter another number:"))
+
+# temp = num1
+# num1 = num2
+# num2 = temp
+# print(f"After swapping:{num1},{num2}")
+
+# x1 = float(input("Enter x1:"))
+# y1 = float(input("Enter y1:"))
+# x2 = float(input("Enter x2:"))
+# y2 = float(input("Enter y2:"))
+
+# euc_distance = ((x1-x2)**2 + (y1-y2)**2)*0.5
+# print("distance is :",euc_distance)
+
+#simple interest calculator
+# p = int(input("Enter amount:"))
+# r = float(input("Enter rate of interest:"))
+# t = int(input("Enter time"))
+
+# interest = p * r * t
+# print("Interest is:",interest-p)
+
+# heads = int(input("Heads-> "))
+# legs = int(input("Legs ->"))
+
+
+#literal - constant value that is stored in variable
+a = 2
+a = 0b1010
+
+# print(a)
+
+# b = 0o456
+# print(b)
+# c =0xA234
+# print(c)
+
+# f1 = 10.34
+# f2 = 12e-3
+# f3 = 1e5
+# print(f1,f2,f3)
+
+# complex1 = 4 + 3j
+# print(complex1)
+
+# a = None
+# print(a)
+# b = True
+# print(b +3)
+
+
+#question no 6
+# heads = int(input("heads->"))
+# legs = int(input("legs->"))
+
+# dogs = (legs - 2 * heads)/2
+# chickens = heads - dogs
+
+# print()
+
+#question 7
+# num = int(input("Enter n :"))
+# sum = (num * (num+1)*(2*num+1))/6
+# print("Sum is:",sum)
+
+#question 8
+# num1 = int(input("enter 1st num:"))
+# num2 = int(input("enter 2nd num:"))
+# n = int(input("Enter n:"))
+# diff = num2 - num1 
+
+# a = num1 + (n-1)*diff
+# print(a)
+
+#question 9
+
+# x1 = int(input("Enter x1:"))
+# y1 = int(input("Enter y1:"))
+# x2 = int(input("Enter x2:"))
+# y2 = int(input("Enter y2:"))
+
+# num = x1 * y2 + y1 * x2
+# den = y1 * y2
+
+# print("{}/{}".format(num,den))
+
+#question 10
+# print("Dimentions of the milk tank")
+# H = int(input("H = "))
+# L = int(input("L = "))
+# B = int(input("B = "))
+# print("Dimensions of the glass")
+# h = int(input("h = "))
+# r = int(input("r = "))
+
+#literals 
+# int_val = 103343
+# bin_val = 0b1001
+# dec_val = 0o234
+# hex_val = 0xA23
+# print(bin_val,type(bin_val))
+# print(dec_val,type(dec_val))
+# print(hex_val,type(hex_val))
+
+# f1 = 1232.4323
+# f2 = 2232e2
+# f3 = 232e-3
+# print(f1,type(f1))
+# print(f2,type(f2))
+# print(f3,type(f3))
+
+# a = 7 + 4j 
+# b = complex(3,4)
+# print(a,type(a),b,type(b))
+
+# bool1 = True
+# bool2 = False
+# print(bool1 + 4)
+# print(bool2 - 4)
+
+a = None
+print(a,type(a))
+a = 100
diff --git a/error_handling.py b/error_handling.py
new file mode 100644
index 0000000..c7c2847
--- /dev/null
+++ b/error_handling.py
@@ -0,0 +1,49 @@
+print("Syntax Error")
+# print "a"
+# print "Hello World"
+# marks = 80
+# if marks>=80:
+# print("A+")
+# if True
+  # print("Asif")
+# fo i in ran(5):
+# class A: 
+
+#index error
+# l=[1,2,3,4,5]
+# print(l[50])
+  
+#module not found error
+# import mata
+# print(math.floor(10.4))
+
+#key error
+# dict1 ={"name":"Asif"}
+# print(dict1["age"])
+
+#typeerror
+# print(1 +"a")
+
+#valueerror
+
+
+
+
+#exceptions
+# with open('sample.txt','w') as f:
+#   f.write("Hello World")
+  
+# with open('sample.txt','r') as f:
+#   print(f.read())
+
+# try:
+#   with open('sample1.txt','r') as f:
+#     print(f.read())
+# except:
+#   print("File not found")
+
+try: 
+  with open('sample.txt','w') as f:
+    f.read()
+except:
+  print("Operation failed")
\ No newline at end of file
diff --git a/file-handling.py b/file-handling.py
new file mode 100644
index 0000000..fb1ef0d
--- /dev/null
+++ b/file-handling.py
@@ -0,0 +1,184 @@
+#if file is not present
+# f = open('./sample.txt','w')
+# f.write("Hello World")
+# f.close()
+# f.write("Asif")
+
+# f = open('./file-1.txt','w')
+# f.write("Hello World")
+# f.close()
+# f.write("My name is Asif")
+
+#write multiline string
+# f = open('./sample1.txt','w')
+# f.write("Hello Emon\nThis is file 1")
+# f.write('\n')
+# f.write("I am 24 years old")
+# f.write("\n")
+# f.write("Closing file")
+# f = open('./file-2.txt','w')
+# f.write('Hello World')
+# f.write('\n')
+# f.write('I am 24 years old')
+# f.close()
+#if file is already present
+# f = open("./sample.txt",'w')
+# f.write("Salmon Bhai is my favourite")
+# f.close()
+
+
+
+#append mode
+# f = open('sample1.txt','a')
+# f.write("Salmon bhai is my favourite")
+# f.close()
+# f = open('./sample1.txt','a')
+# f.write("\n")
+# f.write("Salmon bhai is the don")
+# f.close()
+
+# for i in range(1,11):
+#   f = open('./sample1.txt','a')
+#   f.write(f"Hello {i}\n")
+# f.close()
+
+#write many lines
+# l = ['Hello\n','i am\n','Asif\n','Arfi\n']
+# f = open('./file-2.txt','w')
+# f.writelines(l)
+# f.close()
+# obj1 = 'Hello Python'
+# f = open('./file-2.txt','a')
+# f.writelines(obj1)
+# f.close()
+
+#reading from files - read(),readline()
+# f = open('./file-2.txt','r')
+# s = f.read()
+# print(s)
+# f.close()
+# f = open('file-2.txt','r')
+# print(f.readline())
+# print(f.readline())
+# s1 =f.readline()
+# s2 =f.readline()
+# print(s1)
+# print(s2)
+# f.close()
+
+#reading upto n characters
+# f = open('./sample.txt','r')
+# print(f.read())
+# f = open('./sample1.txt','r')
+# print(f.read(20))
+# f.close()
+
+print("File handling revise")
+
+#if file is not present
+# f = open('sample.txt','w')
+# f.write("Hello Asif")
+# f.close()
+# f.write("I am writing something")
+
+#write multiline strings
+# f = open('sample.txt','w')
+# f.write("Asif")
+# f.write("Emon")
+# f.write("\nProbin")
+# f.close()
+
+#case-2 : if the file is already present
+# f = open('sample.txt','w')
+# f.write("Hello Asif")
+# f.write("\nI am 24 years old")
+# f.close()
+
+# f = open('sample.txt','a')
+# f.write('I am appending')
+# f.write("How are you?")
+# f.close()
+
+print("hi")
+
+# l = ["1","2","3","4","5"]
+# t = ('Asif','emon','hasan')
+# s = "\nASIF"
+# # n = 1231
+# f = open('sample.txt','a')
+# f.writelines(l)
+# f.writelines(t)
+# f.writelines(s)
+# f.writelines(n)
+
+
+#reading from files-read/readlines
+# f = open('sample.txt','r')
+# d = f.read()
+# print(d)
+# d1 = f.readline()
+# d2 = f.readline()
+# print(d1,d2)
+
+
+# f = open('loop.txt','a')
+# for i in range(1,11):
+#   f.write(f"Hello from {i}\n")
+# f.close()
+
+# f = open('loop.txt','r')
+# data = f.read()
+# print(data)
+
+# f = open('loop.txt','r')
+# d1 =f.readline()
+# d2 =f.readline()
+# d3 =f.readline()
+# print(d1)
+# print(d2)
+# print(d3)
+
+# f = open('loop.txt','r')
+# d =f.read(100)
+# print(d)
+
+# print("hello")
+
+# f = open('loop.txt','r')
+# l1 = f.readline()
+# l2 = f.readline()
+# print(l1)
+# print(l2)
+
+#reading entire file using readline
+# f = open('loop.txt','r')
+# while True:
+#   data = f.readline()
+#   if data =='':
+#     break
+#   else:
+#     print(data,end='')
+
+# f.close()
+
+# f = open('file-2.txt','r')
+# while True:
+#   data = f.readline()
+#   if data =='':
+#     break
+#   else:
+#     print(data,end='')
+    
+# f.close()
+
+# with open('file-2.txt','a') as f:
+#   f.write("Salmon bhai")
+# f.write("Hello")
+# with open('file-2.txt','r') as f:
+#   data =f.read()
+#   print(data)
+
+# with open('file-2.txt','r') as f:
+#   data = f.readline()
+#   print(data)
+  
diff --git a/functions.py b/functions.py
new file mode 100644
index 0000000..090be4d
--- /dev/null
+++ b/functions.py
@@ -0,0 +1,119 @@
+#functions and methods
+print("Functions")
+# def sum():
+#   """
+#   calculates sum
+#   input - no input
+#   output - sum of two numbers
+#   created by - asif 
+#   """
+#   a = 10
+#   b = 20
+#   print(a+b)
+
+# sum()
+
+# print(print.__doc__)
+# print(sum.__doc__)
+# print(type.__doc__)
+
+# def is_even(num):
+#   """
+#   fn to calculate even/odd numbers
+#   input - any valid integer
+#   output - even/odd
+#   created - name date
+#   """
+#   if type(num) == int:
+#     if num % 2 ==0:
+#       return "Even"
+#     else:
+#       return "Odd"
+#   else:
+#     return "Wrong value passed"
+# for i in range(1,11):
+#   print(is_even(i))
+
+# print(is_even("Asif"))
+# print(is_even.__doc__)
+
+# arguments
+# def sum (a=10,b=20):
+#   return a + b
+# print(sum(10))
+# def sub(a=0,b=0):
+#   return a - b
+# print(sub(50,20))
+
+# l = [1,2,3]
+# print(l.append(4))
+
+#variable scope
+# def g(y):
+#   print(x)
+#   print(x+1)
+# x = 5
+# g(x)
+# print(x)
+# def f(y):
+#     x = 1
+#     x += 1
+#     print(x)
+# x = 5
+# f(x)
+# print(x)
+# def h(y):
+#     x += 1
+# x = 5
+# h(x)
+# print(x)
+
+# l1 = [1,2,3,4,5,6,7,8,9]
+# l2 = []
+# for i in l1:
+#   if i % 2 ==0:
+#     l2.append(i)
+# print(l2)
+
+# def outer():
+#   print("outer function")
+#   def inner():
+#     print("inner function")
+#   inner()
+# outer()
+# inner()
+# def g(x):
+#     def h():
+#         x = 'abc'
+#     x = x + 1
+#     print('in g(x): x =', x)
+#     h()
+#     return x
+
+# x = 3
+# z = g(x)
+# print(z)
+
+# def g(x):
+#     def h(x):
+#         x = x+1
+#         print("in h(x): x = ", x)
+#     x = x + 1
+#     print('in g(x): x = ', x)
+#     h(x)
+#     return x
+
+# x = 3
+# z = g(x)
+# print('in main program scope: x = ', x)
+# print('in main program scope: z = ', z)
+# l1 = [1,2,3,3,3,3,4,5]
+# l2 = []
+# for i in range(len(l1)-1,-1,-1):
+#   for j in range(0,i):
+#     if l1[i] == l1[j]:
+#       continue
+#     else:
+#       l2.append(l1[j])
+# print(l2)
+    
diff --git a/list.py b/list.py
new file mode 100644
index 0000000..157f7ed
--- /dev/null
+++ b/list.py
@@ -0,0 +1,255 @@
+print("List and methods")
+
+# l = [10,"Asif",25.99,True]
+# print(id(l[0]))
+# print(id(l[1]))
+# print(id(l[2]))
+# print(id(l[3]))
+
+#characteristics of list
+# l = [1,2,3,4]
+# print(l[1])
+# print(l[-1])
+# print(l[0])
+
+# l = [12,34,22]
+# l[0] = 10
+# print(l)
+
+# l = [12,"Asif",23.44]
+# print(l)
+
+# l = [12,34,12]
+# print(l)
+# l.append(100)
+# print(l)
+# l = [12,10,[12,12]]
+# print(l)
+
+# l = [(1,2),"Asif",{"name":"Asif"}]
+# print(l)
+
+# ulti_list = [10,[20,30],"Asif",True,(5,6),{"age":24}]
+# print(ulti_list[0])
+# print(ulti_list[-1])
+# ulti_list[0] = 100
+# print(ulti_list)
+# l1 = [12,3,43]
+# l2 = [12,3,43]
+# print(l1 == l2)
+# print(l1 is l2)
+
+#creating a list
+# l1 = []
+# print(l1)
+# l2 = ["Asif","Probin","Hasan"]
+# print(l2)
+# l3 = [12,34,[1,2],[2,3]]
+# print(l3)
+# print(l3[2][0])
+# l4 = ["Asif",24,True]
+# print(l4)
+# l5 = [[1,2,[5,6]],[0,10,[20,30]]]
+# print(l5[0][2][0],l5[1][2][1])
+# li = list("Asif")
+# print(li)
+# l1 = list((12,34,55))
+# print(l1)
+# l2 = list([12,34,[1,2]])
+# print(l2)
+#accessing items from a list
+l = [10,20,30,40,50]
+# print(l[0])
+# print(l[3])
+# print(l[-1])
+# print(l[len(l)-4])
+# print(l[::])
+# print(l[::-1])
+# print(l[1:4])
+# print(l[0:3])
+# print(l[-5:-1:])
+
+#adding items on a list-append,insert,extend
+# l = [10,20,30,40,50,60]
+# print(l.append(70))
+# print(l)
+# l.extend("Asif")
+# print(l)
+# l.extend([1,2,3])
+# print(l)
+# l.insert(0,'Asif')
+# print(l)
+
+# l1 = [10,20,30,40]
+# l1.insert(1,200)
+# l1.insert(-1,[1,2])
+# print(l1)
+# l1.append(100)
+# print(l1)
+# l1.extend("Asif")
+# print(l1)
+
+#editing items on a list
+# l = [1,2,3,4,5,6,7]
+# l[0] = [12,34]
+# print(l)
+# l[1] = 100
+# print(l)
+# l[0:3]=[1,2,3]
+# print(l)
+
+#deleting items from a list - pop,del,remove,clear
+l = [10,20,30,50,40]
+# l.pop()
+# print(l)
+# l.pop(0)
+# print(l)
+# del l[0]
+# print(l)
+# del l[0:2]
+# print(l)
+# print(l.pop())
+# l.remove(20)
+# print(l)
+# print(l.remove(40))
+# print(l)
+# l.clear()
+# print(l)
+# print(l)
+# del l
+# print(l)
+# del l[0]
+# print(l)
+# del l[0:2]
+# print(l)
+# l.pop()
+# print(l)
+# l.pop(1)
+# print(l)
+# l.remove(50)
+# print(l)
+# l.clear()
+# print(l)
+
+#operation on list
+#arithmetic - +,*
+# l1 = [1,2,3]
+# l2 = [4,5,6]
+# print(l1+l2)
+# print(l1*4)
+
+#list revise
+# l = [12,"Asif",True,10,[1,2,3]]
+# print(id(l[0]))
+# print(id(l[1]))
+# print(id(l[2]))
+
+# l[0] = 10
+# print(l)
+#nested list
+# l = [10,20,30,[1,2,3,[5,6]]]
+# print(l[3][3][1])
+# l = list([1,2,3,4])
+# print(l)
+
+#accessing list items- index,slicing
+l1 = [10,"Asif",True,(1,2,3)]
+# print(l1[0])
+# print(l1[-2])
+# print(l1[len(l1)-3])
+
+# print(l1[::-1])
+# print(l1[::])
+# print(l1[1:3])
+# print(l1[-1:-3:-1])
+
+#adding items to a list-append,extend,insert
+list1 = [10,20,30,40]
+# list1.append(50)
+# list1.append([1,2,3])
+# list1.append(("Asif"))
+# list1.append("Asif")
+# print(list1)
+# list1.extend("Asif")
+# print(list1)
+# list1.extend([1,2,3])
+# print(list1)
+# list1.insert(0,"Asif")
+# print(list1)
+
+#editing items on a list
+#list is mutable - can change any particular value
+# l = [10,"Asif",24.5,True,1,2]
+# l[0] = 100
+# print(l)
+# l[1:3]=["Asif"]
+# print(l)
+
+#deleting items from a list
+# del l[0]
+# print(l)
+# del l[1:3]
+# print(l)
+# del l
+# print(l)
+
+
+
+
+#problem 1
+# list1 = ["M","na","i","Kh"]
+# list2 = ["y","me","s","an"]
+# list3 = []
+
+# for i in range(0,len(list1)):
+#   item = []
+#   item.append(list1[i])
+#   item.append(list2[i])
+#   list3.append(item)
+
+# print(list3)
+
+#problem - 2
+# list1 = [10,20,[300,400,[5000,6000],500],30,40]
+
+# for item in list1:
+#   if isinstance(i,list):
+#     for j in i:
+      
+  
+
+#problem - 4
+# list1 = [1,2,3,4,5,6]
+# list2 = []
+# sum = 0
+# for i in list1:
+#   sum +=i
+#   list2.append(sum)
+  
+# print(list2)
+
+#problem - 3
+# candy_list = ['Jelly Belly','Kit Kat','Double Bubble','Milky Way','Three Musketeers']
+# no_of_items = [10,20,34,74,32]
+
+# for i in range(0,len(candy_list)):
+#   print(f"{candy_list[i]}- {no_of_items[i]}")
+
+#problem - 10
+# list1 = ['campusxIs', 'bestFor', 'dataScientist']
+# for item in list1:
+#   for char in item:
+#     if char.upper() 
+
+#problem - 11
+# list1 = [1,2,3,4,5,1]
+# list2 = [2,3,5,7,8]
+# list3 = []
+
+# for i in range(0,len(list1)):
+#   if list1[i] == list2[i]:
+#     list3.append(list1[i])
+#   else:
+#     list3.append(list2[i])
+
+#list revise
diff --git a/main.py b/main.py
deleted file mode 100644
index 1fb16de..0000000
--- a/main.py
+++ /dev/null
@@ -1,50 +0,0 @@
-print("Section 4 : Operators and expression")
-#arithmetic operatord(+,-,*,/,//,%,**)
-num1 = 40
-num2 = 30
-# add = num1+num2
-# sub = num1-num2
-# multi = num1*num2
-# div = num1/num2
-# print(add,sub,multi,div)
-# floor = num1//num2
-# mod = num1%num2
-# print(floor)
-# print(mod)
-# a,b,c=2,2,3
-# d = a**b**c
-# print(d)
-#floating point numbers
-# a = 25.3
-# b = 6.4
-# floor = a//b
-# mod = a %b
-# sub = a - b
-# print(floor,mod,sub)
-#expression - something that results in values
-# a,b,c = 10,45,22
-# x = a * b +c
-# print(x)
-#operator precedence (),** (right to left),*/ // %,+,-(left to right)
-
-# x = (10+20)*2-4
-# print(x)
-# a=b=c=3
-# print(a**b**c)
-# print(20-5*3/3+10)
-# print(10+20/5)
-#area of a rectangle
-# length = int(input("Enter length:"))
-# width = int(input("Enter width:"))
-# area = length*width
-# print("area is:",area)
-#area of a triangle
-# height = int(input("Enter height:"))
-# base = int(input("Enter base:"))
-# area = int(0.5 * height * base)
-# print("area is",area)
-#area of a trapezium 
-# len = int(input("Enter length:"))
-# wid = int(input("Enter width:"))
-# hei = int(input("Enter height:"))
-# area = 
\ No newline at end of file
diff --git a/oop1.py b/oop1.py
new file mode 100644
index 0000000..0ba8af0
--- /dev/null
+++ b/oop1.py
@@ -0,0 +1,148 @@
+print("Python object oriented programming")
+
+# l = [1,2,3]
+# l.upper()
+
+#oop - class ,object,encapsulation,inheritance,polymorphism,abstraction
+
+# l = [1,2,3]
+# print(type(l))
+
+#class - property/attribute - blueprint of object
+# class Student:
+#   def __init__(self)
+
+# st1 = Student()
+# class Human:
+#   def __init__(self):
+#     print("Human object created")
+    
+# asif = Human()
+
+# class Student:
+#   def __init__(self):
+#     self.name = "Asif"
+#     self.age = 25
+#     self.course ="CSE"
+#     print(f"name:{self.name} age:{self.age} course:{self.course}")
+
+# stu_asif = Student()
+
+# class Student:
+#   def __init__(self,name,age,course):
+#     self.name = name
+#     self.age = age
+#     self.course = course
+#     print(f"name:{self.name} age:{self.age} course:{self.course}")
+
+# student1 = Student("Probin",24,"EEE")
+# student2 = Student("Asif",25,"CSE")
+# print(type(student1))
+    
+# class Atm:
+#   def __init__(self):
+#     self.balance = 0
+#     self.pin =""
+#     self.menu()
+  
+#   def menu(self):
+#     user_input=input("""Hi
+#           How can i help you?
+#           1.Press 1 to create pin
+#           2.Press 2 to change pin
+#           3.Press 3 to debit balance
+#           4.Press 4 to withdraw balance
+#           5.Press 5 to check balance
+#           6.Press 6 to exit\n""")
+    
+#     if user_input =="1":
+#       self.create_pin()
+#     elif user_input =="2":
+#       self.change_pin()
+#     elif user_input =="3":
+#       self.credit_balance()
+#     elif user_input =="4":
+#       self.withdraw_balance()
+#     elif user_input =="5":
+#       self.check_balance()
+#     else:
+#       self.menu()
+      
+#     self.menu()
+      
+#   def create_pin(self):
+#     user_pin = input("Enter pin:")
+#     self.pin = user_pin
+#     print("Pin created successfully")
+    
+#   def change_pin(self):
+#     user_pin = input("Enter your pin:")
+#     if user_pin == self.pin:
+#       new_pin = input("Enter new pin:")
+#       self.pin = new_pin
+#       print("New pin created")
+#     else:
+#       print("Wrong pin")
+  
+#   def credit_balance(self):
+#     user_pin = input("Enter your pin:")
+#     if user_pin == self.pin:
+#       balance = int(input("Enter your balance:"))
+#       self.balance = balance
+#       print("Balance credited successfully")
+#     else:
+#       print("Wrong pin")
+      
+#   def withdraw_balance(self):
+#     user_pin = input("Enter your pin:")
+#     if self.pin == user_pin:
+#       withdraw_balance = int(input("Enter amount to withdraw:"))
+#       if withdraw_balance < self.balance:
+#         self.balance = self.balance - withdraw_balance
+#         print(f"{withdraw_balance} withdrawn successfully")
+#         print(f"current balance is:{self.balance}")
+#       else:
+#         print("You don't have thar much balance")
+        
+#     else:
+#       print("Wrong pin")
+    
+  
+#   def check_balance(self):
+#     print("current balance is {}".format(self.balance))
+  
+
+# obj = Atm()
+
+# class Student:
+#   def __init__(self,name,age,course):
+#     self.name = name
+#     self.age = age
+#     self.course = course
+
+#   def read():
+#     print()
+
+# class Car:
+#   def __init__(self):
+#     print(id(self))
+  
+#   def __str__(self):
+#     print("Object got created")
+  
+# bmw = Car()
+# print(id(bmw))
+# # print(bmw)
+
+# class Car:
+#   def __init__(Self,name,model):
+#     Self.name = name
+#     Self.model = model
+    
+#   def __str__(Self):
+#     return f"Car name:{Self.name} model:{Self.model}"
+
+# bmw =Car("BMW","X6")
+# print(bmw)
+# audi = Car("Audi","R8")
+# print(audi)
\ No newline at end of file
diff --git a/operators.py b/operators.py
new file mode 100644
index 0000000..3ae8b03
--- /dev/null
+++ b/operators.py
@@ -0,0 +1,357 @@
+print("Operators in python")
+
+#operators - symbols to carry out calculations
+# a(operand) +(operator) b(operand)
+
+# a = 100
+# b = 50
+# sum = a + b #150
+# sub = a - b #50
+# multi = a * b #5000
+# div = a / b #2.0
+# exp = a ** b #large number
+# floor_div = a // b #2
+# mod = a % b #0
+
+# print(sum)
+# print(sub)
+# print(multi)
+# print(div)
+# print(exp)
+# print(floor_div)
+# print(mod)
+#operator precedence-(),**,/ * % //,+-
+print(20 + (3*4) - 2 *4 /4)
+# print(2**3**2)
+
+#relational operator - to compare between two things
+# print(4>5) #false
+# print(10<34) #true
+# print(4>=4) #true
+# print(5<=4) #false
+# print(4 == 4) #true
+# print(10 !=30) #true
+# print(2 == 2.00)
+
+
+#logical -and,or,not
+# print(12 and "Asif")
+# print("" and 200)
+
+# print(12 or 13 or 23)
+# print("" or 20 or 23)
+
+# print(not 12)
+
+#bitwise operator - bit by bit kaj kore
+# print( 10 & 4)
+# print(5 & 5)
+# print(10 ^ 5)
+# print(~4)
+
+#assignment operator- =+,=-,*=,/=
+# a = 10
+# b = 5
+# a+=b
+# print(a)
+# a-=b
+# print(a)
+# a*=b
+# print(a)
+
+# a /=b
+# print(a)
+# a %=b
+# print(a)
+# # a++
+# ++a
+# print(a)
+# print(a)
+
+#membership operator-in,not in
+l = [1,2,3,4]
+str1 = "Hello World"
+t = ("Asif",25,True)
+
+# print(1 in l)
+# print(10 not in l)
+# print("A" in str1)
+# print("o" not in str1)
+# print(25 in t)
+# print(False not in t)
+
+# num = int(input("Enter a number:"))
+# dig1 = num % 10
+# num = num //10
+# dig2 = num % 10
+# num = num //10
+# dig3 = num %10
+# num = num //10
+# dig4 = num % 10
+# print(dig1+dig2+dig3+dig4)
+
+#identity operator- is,is not
+# print(12 is 12)
+# print(12 is not 12)
+
+#if else in python
+#login process 
+# email = input("Enter you email:")
+# password = input("Enter password:")
+
+# if email =="asif@gmail.com" and password =="1234":
+#   print("login successful")
+# elif email == "asif@gmail.com" and password !="1234":
+#   print("Wrong password")
+#   password = input("Enter password:")
+#   if password =="1234":
+#     print("Login success")
+# else:
+#   print("Wrong info")
+
+#find the min of 3 given numbers
+# num1 = int(input("Enter a number:"))
+# num2 = int(input("Enter a number:"))
+# num3 = int(input("Enter a number:"))
+
+# if num1 < num3 and num1 < num2:
+#   print(f"{num1} is the min")
+# elif num2 < num1 and num2 < num3:
+#   print(f"{num2} is the min")
+# else:
+#   print(f"{num3} is the min")
+  
+#match case statement
+# x = "monday"
+# match x:
+#   case "Sunday":
+#     print("Today is sunday")
+#   case "Monday":
+#     print("Today is monday")
+#   case "Tuesday":
+#     print("Today is tuesday")
+#   case _:
+#     print("Invalid day")
+
+
+
+#operator tasks
+# ctc = int(input("Enter ctc:"))
+# hra = ctc * 0.1
+# da = ctc * 0.05
+# pf = ctc * 0.03
+# salary = ctc - (hra + da + pf) 
+# if ctc<5:
+#   salary = salary
+# elif ctc >=5 and ctc < 10:
+#   tax = ctc*0.1
+#   salary = salary - tax
+# elif ctc >=10 and ctc <20:
+#   tax = ctc *0.2
+#   salary = salary - tax
+# elif ctc >=20:
+#   tax = ctc * 0.3
+#   salary = salary - tax
+
+#problem - 2
+# angle1 = float(input("enter a angle:"))
+# angle2 = float(input("enter a angle:"))
+# angle3 = float(input("enter a angle:"))
+
+# if (angle1+angle2) > angle3 or (angle2 + angle3) >angle1 or (angle3+angle1) >angle2:
+#   print("Can be a triangle")
+# else:
+#   print("Cannot form a triangle")
+  
+# sum_of_angles = angle1 + angle2 + angle3
+# if sum_of_angles == 180 and (angle1>0 and angle2>0 and angle3>0):
+#   print("Can be a triangle")
+# else:
+#   print("Can't be a triangle")
+  
+# cost = float(input("Enter cost price:"))
+# sell = float(input("Enter selling price:"))
+
+# if cost > sell:
+#   print("Loss")
+# elif cost < sell:
+#   print("Profit")
+# else:
+#   print("Even")
+
+#problem 4 - menu driven program
+# while True:
+#   user_input = input("""
+#   1.cm to ft
+#   2.km to miles
+#   3.USD to BDT
+#   4.exit\n""")
+
+#   if user_input == '1':
+#     cm = float(input("Enter cm value:"))
+#     fit = cm /30.48
+#     print(f"{cm} cm = {fit} ft")
+#   elif user_input =="2":
+#     km = float(input("Enter km value:"))
+#     miles = km /1.61
+#     print(f"{km} km = {miles} miles")
+#   elif user_input == "3":
+#     usd = float(input("Enter usd:"))
+#     bdt = usd * 122.27
+#     print(f"{usd} usd = {bdt} bdt")
+#   else:
+#     print("Exited")
+#     break
+                  
+#problem 5 - fibonacci sequence
+# ini = 0 
+# mid = 1
+# for i in range(1,10):
+  
+
+#problem 6
+# n = int(input("Enter a number:")) 
+# fact = 1
+# for i in range(1,n+1):
+#   fact *= i
+
+# print(f"factorial of {n} is : {fact}")
+
+#problem 7 
+# n = 76542
+# s =""
+# while n % 10 != 0:
+#   dig = n % 10
+#   s +=dig
+#   n = n // 10
+# print(s)
+
+#problem 8 
+# N = int(input())
+# sum = 0
+# i = 0
+# while i < N :
+#   if i % 5 == 0:
+#     continue
+#   else:
+#     sum += i
+  
+#   i +=1
+
+
+
+#control flow 
+#operators
+# exp1 = 34.5 + 45
+# #arithmetic(+,-,*,/,%,//,**)
+# add = 234.5 + 45
+# sub = 23 - 45.0
+# multi = 34 * 45.0
+# div = 45 / 4
+# mod = 34 % 5
+# flo_div = 23 // 10
+# print(add,sub,multi,div,mod,flo_div)
+#precedence - (), **,* / // %,+ -
+#relational operator - ><>=<=.==,!=
+# print(45 > 33)
+# print(34 < 23)
+# print(34>=45)
+# print(44<=23)
+# print(12 == 12)
+# print(12 is 23)
+# print(12.0 == 12)
+# l1 = [12,3,4]
+# l2 = [12,3,4]
+# print(l1 is l2)
+# print(l1 == l2)
+s1 = "Asif"
+s2 = "Asif"
+# print(s1 == s2)
+# print(s1 is s2)
+t1 =(1,2,3)
+t2 =(1,2,3)
+# print(t1 == t2)
+# print(t1 is t2)
+#assignment - +=,-=
+# a = 30
+# a+=30
+# print(a)
+# a-=40
+# print(a)
+# a*=30
+# print(a)
+# a /= 15
+# print(a)
+# a %= 3
+# print(a)
+#logical operator - and,or,not
+# print(true and true)
+# print("Asif" and "23")
+# print("" and 23)
+
+# print(23 or 12)
+# print("" or "Asif")
+
+#membership operator-in,not in
+# print(4 in [1,2,3])
+# print(5 not in (1,234))
+#if else
+
+#palindrome number
+# num = int(input("Enter a number:"))
+# num_str = str(num)
+# num_rev = num_str[::-1]
+# if num_str == num_rev:
+#   print("Palindrome")
+# else:
+#   print("Not palindrome")
+  
+
+#sum of digits
+# num = int(input("Enter a number:"))
+# sum = 0
+# while num % 10 !=0:
+#   dig = num % 10
+#   sum += dig
+#   num = num // 10
+# print(sum)
+
+#count even and odd digits
+# num = int(input("Enter a number:"))
+# even = 0
+# odd = 0
+# while num % 10 !=0:
+#   dig = num % 10
+#   if dig % 2 ==0:
+#     even += 1
+#   else:
+#     odd += 1
+#   num = num // 10
+# print("Even digits:{}".format(even))
+# print("Odd digits:{}".format(odd))
+
+#largest of 3 numbers
+# num1 = int(input("Enter a number:"))
+# num2 = int(input("Enter a number:"))
+# num3 = int(input("Enter a number:"))
+# if num1 > num2 and num1 > num3:
+#   print(f"{num1} is the largest")
+# elif num2 > num3:
+#   print(f"{num2} is the largest")
+# else:
+#   print(f"{num3} is the largest")
+
+#electricity bill calculator
+# units = float(input("Enter units:"))
+# bill = 0
+# if units >=0 and units<=100:
+#   price = 5
+#   bill_under_100 = units * 5
+  
+# if units >=101 and units <= 200:
+#   price = 7
+#   bill_under_200 = bill_under_100 + 
+
+#multiplication table of n
+n = int(input("Enter :"))
+
diff --git a/poridhi-mod1.py b/poridhi-mod1.py
deleted file mode 100644
index afa491b..0000000
--- a/poridhi-mod1.py
+++ /dev/null
@@ -1,13 +0,0 @@
-#extract digits from a number
-n = 7890
-res =[]
-count =0
-while n!=0:
-  dig = n %10
-  count = count + 1
-  res.append(dig)
-  n = n//10
-
-res.reverse()
-print(res)
-print("Digits:",count)
\ No newline at end of file
diff --git a/python-file1 b/python-file1
deleted file mode 100644
index 1185e18..0000000
--- a/python-file1
+++ /dev/null
@@ -1 +0,0 @@
-here is a file to explore how to pull locally
diff --git a/readme.md b/readme.md
index ec8e50e..1fa5575 100644
--- a/readme.md
+++ b/readme.md
@@ -1 +1,10 @@
+#Python Pratice Code
 Here is a readme file to explore pull request
+Here is a readme line for practicting git merge
+
+#heading1 
+##heading2
+###heading3
+####heading4
+#####heading5
+######heading6
diff --git a/section1.py b/section1.py
deleted file mode 100644
index 96b0c89..0000000
--- a/section1.py
+++ /dev/null
@@ -1,26 +0,0 @@
-# print("Getting started")
-# message = "Hello Python"
-# print(message)
-print("Python data types and variables")
-# int_var = 10
-# float_var = 34.56
-# str_var = "Asif"
-# bool_var = True
-# print(int_var,type(int_var))
-# print(float_var,type(float_var))
-# print(str_var,type(str_var))
-# print(bool_var,type(bool_var))
-#assigning multiple values
-# a,b,c = 10,"Python",False
-# print(a,b,c)
-# print(id(a),id(b),id(c))
-# a=b=c=10
-# print()
-dig = 7895
-ls =[]
-while dig!=0:
-  last_dig = dig % 10
-  ls.append(last_dig)
-  dig = dig //10
-
-print(ls)
\ No newline at end of file
diff --git a/section3.py b/section3.py
deleted file mode 100644
index 476902d..0000000
--- a/section3.py
+++ /dev/null
@@ -1,129 +0,0 @@
-import sys 
-print("Variables and Data types")
-# length = 10
-# breadth = 20
-# area = length* breadth
-# print(area)
-#variable 
-# num1 = 10
-# num2 = 23
-#data type
-# int_var = 20
-# float_var = 345.45
-# bool_var = True
-# str = "Python"
-# print(int_var,type(int_var))
-# print(float_var,type(float_var))
-# print(bool_var,type(bool_var))
-# print(str,type(str))
-#multiple variable declaration
-# a,b,c = "Asif",24,True
-# print(id(a))
-# print(id(b))
-# print(id(c))
-# a=b=c=10
-# print(id(a),id(b),id(c))
-# x = 10
-# print(x,id(x))
-# x ="Afiya"
-# print(x,id(x))
-# x = False
-# print(x,id(x)) 
-#naming convention
-# prod_id = 235335
-# cust_id = 33
-# first_name ="Md Asif"
-
-#python data types - numeric(int,float,boolean,complex)
-# int_var = 234
-# float_var = 3453.564
-# bool_var = True
-# complex_var = 2 + 3j
-# print(int_var,type(int_var))
-# print(float_var,type(float_var))
-# print(bool_var,type(bool_var))
-# print(complex_var,type(complex_var))
-#sequence - list,tuple,string
-# l = [23,11.22,True,"Asif"]
-# for x in l:
-#   print(x)
-
-# print(l[0],l[1],l[2],l[3])
-# #list is mutable
-# l[1]=200.40
-# l[3] = "Emon"
-# print(l)
-#tuple - immutable
-# t = (12,22.334,False,"Python")
-# for x in t:
-#   print(x)
-# t[0]=10
-# print(t)
-# str1 = 'Python'
-# str2 = "Javascript"
-# str3 = '''Golang'''
-# print(str1,str2,str3)
-# for x in str1:
-#   print(x)
-
-# print(str1[0],str1[1])
-# str[2]='j'
-
-# s ={12,34,"Asif",True}
-# for x in s:
-#   print(x)
-
-# # print(s[0])
-# s[2]=12
-# str ="I love Python"
-
-# num1 = 2343242423422
-# print(type(num1))
-# num2 = 2342
-# print(sys.getsizeof(num1))
-# print(sys.getsizeof(num2))
-# float_val = 234.453590383030
-# print(sys.getsizeof(float_val))
-# bool_val = True
-# print(sys.getsizeof(bool_val))
-# x = True
-# y = False
-# print(int(x),int(y))
-# print(type(x),type(y))
-
-# complex_val = 2 + 3j
-# print(complex_val)
-# print(type(complex_val))
-# print(sys.getsizeof(complex_val))
-# c = complex(2,3)
-# print(c)
-# val = complex(23,34)
-# print(val)
-# var1 = complex(2,3)
-# var2 = complex(3,4)
-# print(var1+var2)
-# a = 10
-# b = 20
-# c = a +b
-# print(c)
-#integer literal 
-# a = 10
-# b = 123_234_122
-# print(a,b)
-# c = 12_22_10_234
-# # print(c)
-# f = 123.4533
-# print(f)
-# f1 = 22_2.22_42
-# print(f1)
-# f2 = 23E2
-# print(f2)
-# bool1 = True
-# bool2 = False
-# complex1 = 3 + 2j
-# str1 = 'String1'
-# str2 = "String2"
-# str3 = '''String3'''
-# txt1 = "Asif's age is 24"
-# txt2 = 'quote"jneajgnaj"'
-# print(txt1,txt2)
diff --git a/section4.py b/section4.py
deleted file mode 100644
index 949fd7d..0000000
--- a/section4.py
+++ /dev/null
@@ -1,23 +0,0 @@
-print("Operators and expressions")
-#arithemtic(+,-,*,/,//,%,**)
-# num1 = 123
-# num2 = 345
-# add = num1 + num2 
-# sub = num1 - num2
-# multi = num1 * num2
-# div = num1 / num2 
-# print(add,sub,multi,div)
-# num1 = 455
-# num2 = 7
-# mod = num1%num2
-# print(mod)
-# flo = num1 //num2
-# print(flo)
-# x = 3
-# y = 4
-# z = 5
-# exp = x**y
-# print(exp)
-#precedence -(),**(r-l), /* // % ,+-(l-r)  
-# exp1 = 5 + 2*3 - 8/2
-# print(exp1)
diff --git a/section5.py b/section5.py
deleted file mode 100644
index 4e7c089..0000000
--- a/section5.py
+++ /dev/null
@@ -1,27 +0,0 @@
-print("Conditional Statements")
-#relational operator - <,<=,>,>=,==,!=
-# print(4>5)
-# print(5<8)
-# print(10==10)
-# print(23!=22)
-# age = 17
-# if age>=18:
-#   print("He can drive")
-# else:
-#   print("He can't drive")
-# num = int(input("Enter a number:"))
-# if num>=0:
-#   print(num," is positive")
-# else:
-#   print(num," is negative")
-
-# var1 = "Asif"
-# var2 = False
-# print(var1 or var2)
-# a =8
-# print(not a)
-# marks = 30
-# if marks>=45 and marks <=100:
-#   print("passed")
-# else:
-#   print("failed")
\ No newline at end of file
diff --git a/sets.py b/sets.py
new file mode 100644
index 0000000..77cd6bc
--- /dev/null
+++ b/sets.py
@@ -0,0 +1,32 @@
+print("sets")
+#s1 = {12,34,10,"Asif",True}
+#print(s1)
+# print(s1)
+# s1 = set()
+# print(s1)
+
+#creating sets
+s1 = {}
+# print(s1,type(s1))
+s1 = set()
+#print(s1,type(s1))
+s2 = {12,3,23,12}
+# print(s2)
+#s3 = {1,2,3,4,{1,2}}
+s4 = {12,3,"Asif",True,(1,2,3)}
+print(s4)
+
+# s5 = set([2,3,4,4,6433,3,53535,3])
+# s6 = set("Asif")
+# print(s5,s6)
+
+# s1 = {1,2,3}
+# s2 = {3,2,1}
+# print(s1==s2)
+
+#accessing items
+s1 = {"Asif",24,True,23.99}
+# print(s1[0])
+# print(s1[0:3])
+# s1[0] = 10
+
diff --git a/store_sales.csv b/store_sales.csv
new file mode 100644
index 0000000..0318ba6
--- /dev/null
+++ b/store_sales.csv
@@ -0,0 +1,101 @@
+order_id,customer_name,product,category,quantity,unit_price,total,order_date,country,payment_method
+1,Tanvir,Jeans,Fashion,4,1500,6000,2025-01-18,Nepal,Card
+2,Tanvir,Jeans,Fashion,5,1500,7500,2025-01-12,Pakistan,Card
+3,Naila,Keyboard,Electronics,4,1200,4800,2025-01-22,Nepal,Card
+4,Karim,Keyboard,Electronics,3,1200,3600,2025-01-23,Bangladesh,Card
+5,Nahid,Keyboard,Electronics,1,1200,1200,2025-01-22,Nepal,Cash
+6,Ayesha,Mobile,Electronics,1,25000,25000,2025-01-11,Nepal,Cash
+7,Imran,Jeans,Fashion,1,1500,1500,2025-02-03,Nepal,UPI
+8,Karim,Headphones,Electronics,2,3500,7000,2025-01-05,Pakistan,Card
+9,Rahim,Headphones,Electronics,5,3500,17500,2025-01-01,India,UPI
+10,Rafi,Headphones,Electronics,2,3500,7000,2025-01-11,Bangladesh,Card
+11,Imran,T-Shirt,Fashion,2,500,1000,2025-01-26,Bangladesh,UPI
+12,Imran,Jeans,Fashion,3,1500,4500,2025-01-11,Nepal,Cash
+13,Asif,Headphones,Electronics,1,3500,3500,2025-01-05,Nepal,Card
+14,Asif,Mouse,Electronics,5,600,3000,2025-01-01,Nepal,Card
+15,Karim,Keyboard,Electronics,5,1200,6000,2025-01-14,Nepal,Card
+16,Naila,Jeans,Fashion,3,1500,4500,2025-01-25,Pakistan,Cash
+17,Rahim,Keyboard,Electronics,5,1200,6000,2025-01-23,Pakistan,UPI
+18,Naila,Mouse,Electronics,4,600,2400,2025-01-21,Sri Lanka,UPI
+19,Hasan,Headphones,Electronics,2,3500,7000,2025-01-31,Nepal,Card
+20,Sadia,Shoes,Fashion,3,2000,6000,2025-01-13,Nepal,Card
+21,Hasan,Mouse,Electronics,3,600,1800,2025-02-05,Bangladesh,Cash
+22,Karim,Mouse,Electronics,3,600,1800,2025-01-24,Sri Lanka,Cash
+23,Sadia,Shoes,Fashion,2,2000,4000,2025-02-02,Pakistan,Cash
+24,Nahid,T-Shirt,Fashion,4,500,2000,2025-02-02,Bangladesh,Card
+25,Imran,Mobile,Electronics,1,25000,25000,2025-01-23,Pakistan,UPI
+26,Hasan,T-Shirt,Fashion,2,500,1000,2025-02-02,Bangladesh,UPI
+27,Ayesha,Keyboard,Electronics,2,1200,2400,2025-01-15,Pakistan,Cash
+28,Imran,Mouse,Electronics,2,600,1200,2025-01-18,Bangladesh,Cash
+29,Hasan,Keyboard,Electronics,4,1200,4800,2025-01-04,Nepal,Cash
+30,Naila,T-Shirt,Fashion,1,500,500,2025-02-03,Bangladesh,Cash
+31,Naila,Shoes,Fashion,3,2000,6000,2025-01-10,Nepal,Card
+32,Tanvir,Headphones,Electronics,5,3500,17500,2025-01-09,Bangladesh,Card
+33,Nahid,Keyboard,Electronics,2,1200,2400,2025-01-03,Nepal,UPI
+34,Sadia,Jeans,Fashion,3,1500,4500,2025-01-07,Sri Lanka,Card
+35,Naila,Mouse,Electronics,3,600,1800,2025-01-08,Pakistan,Card
+36,Karim,T-Shirt,Fashion,2,500,1000,2025-01-30,Bangladesh,Cash
+37,Karim,Shoes,Fashion,5,2000,10000,2025-01-20,Nepal,UPI
+38,Ayesha,Keyboard,Electronics,5,1200,6000,2025-02-03,Bangladesh,UPI
+39,Rahim,T-Shirt,Fashion,1,500,500,2025-02-03,Nepal,Cash
+40,Naila,Keyboard,Electronics,3,1200,3600,2025-01-13,India,Cash
+41,Tanvir,Mobile,Electronics,1,25000,25000,2025-01-25,India,Card
+42,Asif,Jeans,Fashion,1,1500,1500,2025-01-06,Nepal,Cash
+43,Nahid,T-Shirt,Fashion,5,500,2500,2025-01-28,Bangladesh,UPI
+44,Hasan,Mobile,Electronics,1,25000,25000,2025-01-28,Bangladesh,Cash
+45,Asif,Mobile,Electronics,1,25000,25000,2025-01-16,Pakistan,Cash
+46,Rafi,Mouse,Electronics,1,600,600,2025-01-04,Pakistan,UPI
+47,Tanvir,Keyboard,Electronics,1,1200,1200,2025-01-24,Sri Lanka,UPI
+48,Imran,Mouse,Electronics,3,600,1800,2025-01-09,Bangladesh,Card
+49,Hasan,Keyboard,Electronics,1,1200,1200,2025-01-12,India,Cash
+50,Hasan,Jeans,Fashion,2,1500,3000,2025-01-27,Pakistan,UPI
+51,Rafi,Keyboard,Electronics,4,1200,4800,2025-01-31,Bangladesh,Cash
+52,Ayesha,Shoes,Fashion,1,2000,2000,2025-01-28,Pakistan,Cash
+53,Tanvir,Headphones,Electronics,4,3500,14000,2025-01-21,Bangladesh,Card
+54,Asif,Shoes,Fashion,3,2000,6000,2025-01-13,India,Cash
+55,Asif,Mouse,Electronics,5,600,3000,2025-01-10,Nepal,Cash
+56,Hasan,Headphones,Electronics,5,3500,17500,2025-01-09,Pakistan,Cash
+57,Nahid,Mouse,Electronics,2,600,1200,2025-01-15,Sri Lanka,Card
+58,Karim,T-Shirt,Fashion,2,500,1000,2025-01-14,Pakistan,Cash
+59,Asif,Mobile,Electronics,5,25000,125000,2025-01-30,Bangladesh,UPI
+60,Imran,Shoes,Fashion,3,2000,6000,2025-01-07,Nepal,Cash
+61,Sadia,Keyboard,Electronics,4,1200,4800,2025-01-14,Nepal,UPI
+62,Nahid,Headphones,Electronics,3,3500,10500,2025-01-15,Sri Lanka,Card
+63,Naila,Keyboard,Electronics,1,1200,1200,2025-01-01,India,UPI
+64,Nahid,Mouse,Electronics,5,600,3000,2025-01-15,Sri Lanka,Cash
+65,Hasan,Mouse,Electronics,1,600,600,2025-01-08,Bangladesh,Cash
+66,Ayesha,Jeans,Fashion,2,1500,3000,2025-01-31,Nepal,Card
+67,Sadia,Headphones,Electronics,2,3500,7000,2025-01-11,Sri Lanka,UPI
+68,Karim,Mouse,Electronics,2,600,1200,2025-01-27,Sri Lanka,UPI
+69,Sadia,Headphones,Electronics,4,3500,14000,2025-02-03,India,Cash
+70,Imran,Jeans,Fashion,2,1500,3000,2025-02-05,India,Cash
+71,Nahid,Mobile,Electronics,1,25000,25000,2025-01-08,Pakistan,Cash
+72,Nahid,T-Shirt,Fashion,4,500,2000,2025-02-04,India,UPI
+73,Rahim,T-Shirt,Fashion,1,500,500,2025-01-02,Nepal,UPI
+74,Nahid,Keyboard,Electronics,5,1200,6000,2025-01-11,Nepal,Card
+75,Hasan,Headphones,Electronics,5,3500,17500,2025-01-10,Bangladesh,Cash
+76,Ayesha,Headphones,Electronics,4,3500,14000,2025-01-11,Pakistan,Cash
+77,Ayesha,Mobile,Electronics,2,25000,50000,2025-02-03,India,Cash
+78,Ayesha,Headphones,Electronics,4,3500,14000,2025-01-17,India,Card
+79,Ayesha,Shoes,Fashion,1,2000,2000,2025-01-28,Bangladesh,UPI
+80,Rahim,Mobile,Electronics,3,25000,75000,2025-01-23,Bangladesh,UPI
+81,Tanvir,Shoes,Fashion,2,2000,4000,2025-01-17,India,Card
+82,Naila,Mobile,Electronics,3,25000,75000,2025-01-22,Sri Lanka,Cash
+83,Ayesha,Headphones,Electronics,4,3500,14000,2025-01-21,Pakistan,UPI
+84,Naila,T-Shirt,Fashion,3,500,1500,2025-01-19,India,Card
+85,Rafi,Jeans,Fashion,1,1500,1500,2025-01-18,Pakistan,Card
+86,Karim,Keyboard,Electronics,3,1200,3600,2025-01-05,India,Cash
+87,Rahim,Shoes,Fashion,1,2000,2000,2025-01-14,Nepal,Card
+88,Ayesha,Headphones,Electronics,3,3500,10500,2025-01-12,Pakistan,Cash
+89,Rafi,Mobile,Electronics,2,25000,50000,2025-01-14,Pakistan,Card
+90,Naila,Jeans,Fashion,4,1500,6000,2025-01-03,Pakistan,Card
+91,Hasan,Mouse,Electronics,2,600,1200,2025-01-15,Pakistan,Card
+92,Asif,Mouse,Electronics,5,600,3000,2025-01-10,Pakistan,Cash
+93,Nahid,T-Shirt,Fashion,5,500,2500,2025-01-26,Nepal,Cash
+94,Nahid,Shoes,Fashion,2,2000,4000,2025-01-25,India,Card
+95,Tanvir,Mobile,Electronics,4,25000,100000,2025-01-11,Sri Lanka,UPI
+96,Nahid,Shoes,Fashion,2,2000,4000,2025-01-27,Pakistan,Cash
+97,Tanvir,Shoes,Fashion,1,2000,2000,2025-01-05,Nepal,UPI
+98,Asif,Mouse,Electronics,2,600,1200,2025-02-01,Nepal,Card
+99,Ayesha,Headphones,Electronics,5,3500,17500,2025-01-22,Pakistan,Cash
+100,Rahim,Jeans,Fashion,4,1500,6000,2025-01-09,Pakistan,UPI
diff --git a/string.py b/string.py
index 4da5536..6129aff 100644
--- a/string.py
+++ b/string.py
@@ -1,23 +1,340 @@
-print("String and String methods")
-str1 = 'Hello Python'
-str2 = "Hello Bangladesh"
-str3 = '''Hello Bro'''
-# print(str1,str2,str3)
-# print(str1[0],str1[1],str1[2])
-# print(str2[-1],str2[-2],str2[-3])
-# for x in str1:
-#   print(x)
-# for y in str2:
-#   print(y)
-# for z in str3:
-#   print(z)
-# print(len(str1),len(str2),len(str3))
-
-# for i in range(len(str1)):
-#   print(str1[i])
+print("String and methods")
+
+# s1 = 'Hello Asif'
+# s2 = "Hello Emon"
+# s3 = """I am 
+#       24 years old"""
+
+# print(s1,s2,s3)
+# s4 = str(2443.4)
+# print(s4,type(s4))
+
+# print("Hi i am 30 year's old")
+# print('Hlw How are "you"')
+
+#accessing stings-indexing.slicing
+s = "Hello Python"
+# print(s[0])
+# print(s[6])
+# print(s[-1])
+# print(s[len(s)-6])
+
+# print(s[15])
+
+#slicing
+# print(s[::])
+# print(s[::-1])
+# print(s[0:6:2])
+# print(s[1:5])
+# print(s[-1:-5:-1])
+# print(s[-1::])
+# print(s[-6:])
+# print(s[-5:-1])
+
+#editing and deleting strings
+# s[0] ="A"
+# s1 = s[0]
+# print(s1)
+# s2 = s[1:4]
+# print(s2)
+# del s[0]
+# del s[0:5]
+# del s
+# print(s)
+
+#operations on string
+# print("Asif"+" "+"Arfi")
+# print("Delhi"+ "Mumbai")
+# print("Asif"*3)
+# print("Asif"-23)
+# print("*"*50)
+# print("Asif">"Cinema")
+# print("Emon">)
+
+#relational operator
+# print("Asif"=="Asif")
+# print(12 == 12.00)
+# print("Dhaka"!="dhaka")
+# print("Asif">"Asif")
+# print("Asif"<"Emon")
+# print('qwer'>="1234")
+
+# print("Asif" and "Afiya")
+# print("" and "A")
+
+# print("Asif" or 12)
+# print(False and "Asif")
+
+# print(not "")
+# print(not "Asif")
+
+# for i in "Hello World":
+#   print(i)
+  
+# s = "Asif is 24 years old"
+# for i in range(0,len(s)):
+#   print(s[i])
+
+#functions-len,min,max,sorted
+s = "Hello Asif"
+# print(len(s))
+# print(max(s))
+# print(min(s))
+# print(max(''))
+# print(sorted(s,reverse=True))
+
+#more functions - capitalize,title,upper,lower,swapcase
+s = "hello WoRld"
+# print(s.capitalize())
+# print(s.title())
+# print(s.upper())
+# print(s.lower())
+# print(s.swapcase())
+
+#count/index/find
+# print(s.count('o'))
+# print(s.count('l'))
+# # print(s.index("7"))
+# print(s.find('w'))
+# print(s.find(''))
+
+#find the length
+
+# s = input("Enter a string:")
+
+# count = 0
+# for i in s:
+#   count +=1
+#   print(i)
+
+# print("length is:",count)
+
+# s = input('Enter email:')
+
+# username = ""
+# for i in s:
+#   if i =="@":
+#     break
+#   else:
+#     username +=i
+  
+# print("username:",username)
+
+# s = input("enter a string:")
+# c = input("enter a character:")
+# count =0
+# for x in s:
+#   if x == c:
+#     count +=1
+    
+# print(c," count:",count)
+
+# s = input("enter the string:")
+# c = input("enter the character to remove:")
+
+# str1 = ""
+
+# for x in s:
+#   if x ==c:
+#     continue
+#   else:
+#     str1+=x
+    
+# print("modified string:",str1)
+
+
+#string revise
+# s1 = 'Hello Asif'
+# s2 = "Hello Python"
+# s3 = """Hi
+#   i am asif"""
+# print(s1,s2,s3)
+# print("Hello I am 24 year's old")
+# print('Hello "Probin ')
+# s1 = str(2+3j)
+# print(s1)
+
+#accessing string - index,slicing
+s1 = "Hello Bangladesh"
+# print(s1[0])
+# print(s1[-4])
+# print(s1[len(s1)-3])
+# print(s1[1:4])
+# print(s1[::-1])
+# print(s1[::])
+# print(s1[:4])
+# print(s1[-1:-5:-1])
+
+#string is immutable - can't edit the string
+s1 = "Hello Bangladesh"
+# s1[0] = "As"
+# print(s1)
+# s1[1:3] = "Asif"
+# print(s1[0])
+# del s1[0] 
+# del s1
+# print(s1)
+#operations on string
+#arithmetic - +/*
+s1 = "Hello"
+# print(s1*3)
+# print(s1 + "Asif" + 23)
+# print("Mumbai"+"Delhi")
+# print("Asif"+"Asif")
+#relational - <,<=,>=,>,==,!=
+# print("Asif">"Himel")
+# print("Asif"<"probin")
+# print("Boss" == "Boss")
+# print("Boss">"Asif")
+# print("Asif"!="asif")
+# print("Cat">"Catch")
+# print("cat">"CAT")
+#string formatting
+# name = "Asif"
+# age = 24
+# print(f"My name is {name} and age is {age}")
+# str1 ="My name is {} and age is {}".format(name,age)
+# print(str1)
+
+# print("Asif" and "Hasan" and "Probin")
+# print("" and "Asif" and "9")
+# print("Asif" or False)
+# print("" or "AS")
+# print(not "Asif")
+# print(not "")
+# for i in "Hello World":
+#   print(i)
+
+# for i in range(1,11):
+#   print(f"Hello World {i}")
+
+#membership operator - in,not in
+# print("H" in "Hello")
+# print("D" in "delhi")
+# print("a" not in "Asif")
+
+#common function - len,max,min,sorted
+s1 = "hello world"
+# print(len(s1))
+# print(max(s1))
+# print(min(s1))
+# print(sorted(s1,reverse=True))
+# print(s1.capitalize())
+# print(s1.title())
+# print(s1.upper())
+# print(s1.lower())
+# print(s1.swapcase())
+# print(s1.count("o"))
+
+#find the length of a given string
+# s = input("Enter a string:")
+# counter = 0
+# for i in s:
+#   counter += 1
   
-# for i in range(len(str2)):
-#   print(str2[i])
+# print(f"length of string is : {counter}")
 
-# for i in range(len(str3)):
-#   print(str3[i])
\ No newline at end of file
+# email = input("Enter your email:")
+
+#string revise
+
+# str1 = 'Hello Asif'
+# str2 = "Hello Python"
+# str3 ="""Multiline
+# string"""
+# print(str1,str2,str3)
+# print("Asif 's")
+# print('Asif"ssf')
+# str1 = str("Asif")
+# print(str1)
+s1 = "Hello Python"
+# print(s1[4])
+# print(s1[-4])
+# print(s1[len(s1)-3])
+#slicing - [::]
+# print(s1[1:5])
+# print(s1[::-1])
+# print(s1[::])
+# print(s1[:5])
+# print(s1[-3:-5:-1])
+
+#s1[0] ="A"
+# s2 = s1[0:4]
+# print(s2)
+# s = "Asif"
+# # del s[0]
+# del s
+# print(s)
+#operations on string
+# print("Asif"+" "+"Asif")
+# print("Asif"*3)
+# print("Asif">="asif")
+# print("Dhaka"<"Pune")
+# print("cat">"catch")
+#print("Asif"=="asifa")
+# print("Asif"and"Asifa")
+# print("sif"and"")
+# print("" and "Asif")
+# print("Asif"or"Shifa")
+#print(not 23)
+# s1 = "Hello Asif"
+# for i in s1:
+#   print(i)
+#print("D" in "Deshi")
+# print(12 and 23 and 34)
+# print(23 and "" and 34)
+#common functions-min,max,len,sorted
+# s1 = "Hello Asif"
+# print(len(s1))
+# print(max(s1))
+# print(min(s1))
+# print(sorted(s1,reverse=True))                                                
+# s1 = "hello World"
+# print(s1.capitalize())
+# print(s1.upper())
+# print(s1.lower())
+# print(s1.title())
+# print(s1.swapcase())
+# s2 = "Hello Python"
+# print(s2.swapcase())
+# print(s2.lower())
+# print(s2.upper())
+# print(s2.title())
+# print(s2.capitalize())
+#string formatting- format,f-string
+# name = "Asif"
+# age = 25
+# print("My name is {} and age is {}".format(name,age))
+# print(f"My name is {name} and age is {age}")
+#functions to check if a string meets a criteria
+# s = "HelloWorld"
+# print(s.isalnum())
+# s = "!123Asif"
+# print(s.isalnum())
+
+
+
+
+
+# email = "haque.mdasif1501@gmail.com"
+# username =""
+# for i in email:
+#   if i =='@':
+#     break
+#   else:
+#     username +=i
+# print("Username :{}".format(username))
+
+#count the frequency of a particular character in a string
+# s = "hello how are you"
+# char = 'h'
+# count = 0
+# for i in s:
+#   if i == char:
+#     count +=1
+
+# print(f"Frequency:{count}")
+  
+#remove a particular character from a string
+# s = input("Enter a string:")
+# char = input("Enter a char:")
diff --git a/strings.py b/strings.py
new file mode 100644
index 0000000..796c146
--- /dev/null
+++ b/strings.py
@@ -0,0 +1,49 @@
+#creating string
+# print('Hello World')
+# print("Hello Python")
+# print("""I am asif""")
+# print("I am 24 year's old")
+# print('I am " Asif')
+# print("""Hello 
+#       My name is
+#       Asif""")
+# print(str(23))
+# li = str([12,3,2])
+# print(li,type(li))
+
+#accessing the string - indexing/slicing
+s1 = "Hello Bangladesh"
+# print(s1[0])
+# print(s1[4])
+# print(s1[-2])
+# print(s1[len(s1)-5])
+# print(s1[::])
+# print(s1[::-1])
+# print(s1[2:6:2])
+# print(s1[:5])
+# print(s1[-1:-5:-1])
+# print(s1[-5:])
+# print(s1[-7:-3])
+
+#edit and delete a string
+#string is immutable , can't change particular value
+s1 = "Hello Python"
+# s1[0] ="A"
+# print(s1)
+# s2 = s1[:5]
+# print(s2)
+# s3 = s1[0]
+# print(s3)
+# del s1[0]
+# del s1[:5]
+# del s1
+# print(s1)
+
+#operation on string
+# s1 = "Asif"
+# s2 = "23"
+# print(s1 + s2)
+# print(s1 * 2)
+# print("*" * 10)
+
+#relational operator
diff --git a/tuples.py b/tuples.py
new file mode 100644
index 0000000..ad2a9fd
--- /dev/null
+++ b/tuples.py
@@ -0,0 +1,380 @@
+print("Tuples")
+t1 =(12,11,22,11)
+# print(t1[0])
+# print(t1[-1])
+# t1[3]=10
+#creating a tuple
+# t1 =()
+# print(t1)
+# t2 =(1)
+# print(t2,type(t2))
+# t3 = (1,)
+# print(t3,type(t3))
+# t4 = (12,32,242,244)
+# print(t4)
+# t5 = ("Asif",24,True,[1,2,3])
+# print(t5)
+# t6 = (1,2,3,4,(5,6,7))
+# print(t6)
+# t7 = tuple("Asif")
+# print(t7)
+# t8 = tuple([1,2,3,5])
+# print(t8)
+
+#accessing tuples - indexing,slicing
+t1 =("Asif",24,19.99,True,10,20)
+# print(t1[0])
+# print(t1[-1])
+# print(t1[-3])
+# print(t1[::])
+# print(t1[1:3])
+# print(t1[::-1])
+# t1[6] ="A"
+
+#editing items
+t1 = (12,3,4,2,23,22)
+# t1[4] = 22
+
+#adding r editing,deleting korte gele type error dekhai
+#deleting items
+# del t1[2]
+# del t1
+# print(t1)
+#operation on tuple
+#arithmetic - + ,*
+t1 = (1,2,3)
+t2 = (1,2,3)
+# print(t1+t2)
+# print(t1*3)
+#membership - in,not in
+# print(1 in t1)
+# print(10 not in t1)
+# print(5 in t2)
+# print(1 not in t2)
+# print(t1 == t2)
+# print(t1 is t2)
+# for i in t1:
+#   print(i)
+
+# t1 = (1,2,3,(10,20),(30,40),(50,60))
+# for i in t1:
+#   if isinstance(i,tuple):
+#     for j in i:
+#       print(j)
+#   else:
+#     print(i)
+
+#tuple functions - max,min,len,sorted,sum
+t1 =(1,2,3,4,5,6)
+t2 =("Asif",24,True,19.99)
+# print(max(t1))
+# print(max(t2))
+# print(min(t1))
+# print(min(t2))
+# print(len(t1))
+# print(len(t2))
+# print(sorted(t1,reverse=True))
+# print(sorted(t2))
+# print(sum(t1))
+
+
+#tuple revise
+# tu = (12,34,22)
+# tu[0] = 10
+# print(tu)
+tu =("Asif",24,12,12)
+# print(tu[0])
+# print(tu[1])
+# print(tu[2])
+# print(tu[3])
+
+#creating a tuple
+# t1 = ()
+# print(t1,type(t1))
+# t2 = ("Asif")
+# print(t2,type(t2))
+# t3 = (23,)
+# print(t3,type(t3))
+
+# #homo 
+# t4 = (10,20,30,40)
+# print(t4)
+# #hetaro
+# t5 = ("Asif",24,True,[1,2,3])
+# print(t5)
+# #2D
+# t6 = ("Asif",24,(1,2))
+# print(t6)
+# #tuple constructor
+# t7 = tuple("Asif")
+# print(t7)
+# t8 = tuple((10,20,30))
+# print(t8)
+
+#accessing items-indexing,slicing
+t1 = ("Asif",24,True,[1,2,3])
+# print(t1[0])
+# print(t1[-1])
+# print(t1[len(t1)-3])
+
+# print(t1[::])
+# print(t1[::-1])
+# print(t1[0:3])
+# print(t1[-4:])
+# print(t1[-5:-4:-1])
+
+#editing items-cannot edit because tuple is immutable
+# tu = (10,20,30,40)
+# tu[0] = 100
+# print(tu)
+#adding items is not possible
+# tu = (1,2,3,4)
+# tu[10]=10
+
+#deleting items
+# t = (10,20,30,40)
+# del t
+# print(t)
+
+#operations on tuple
+t1 = (10,20,30)
+t2 = (10,20,30)
+# print(t1 + t2)
+# # print(t1 * t2)
+# print((10,20)* 5)
+# print(t1 == t2)
+# print(t1 == t2)
+# print(5 in t1)
+# print(10 in t1)
+# print(5 not in t1)
+# for i in t1:
+#   print(i)
+
+#tuple functions- max/sum/min/max/len/sorted
+# t1 = (12,3,4,2,5)
+# t2 = ("Asif","Probin","Emon")
+# print(len(tu))
+# print(max(t1))
+# # print(max(t2))
+# print(min(t1))
+# # print(min(t2))
+# print(sum(t1))
+# # print(sum(t2))
+# print(sorted(t1,reverse=True))
+# print(sorted(t2))
+
+# print(t1.count(2))
+
+# t1 = (10,20,30,40,30)
+# print(t1.count(30))
+# print(t1.index(50))
+
+t1 = (10,20,("Asif","Probin"),(1,2,3),(20,30,40))
+# for i in t1:
+#   for j in t1:
+#     if isinstance(j,tuple):
+#       print(j)
+#   print(i)
+# for item in t1:
+#   if isinstance(item,tuple):
+#     for j in item:
+#       print(j)
+#   else:
+#     print(item)
+# t2 = ("Asif",(10,20),(1,2,3),[5,10,15])
+# for i in t2:
+#   if isinstance(i,tuple or list):
+#     for j in i:
+#       print(j)
+#   else:
+#     print(i)
+
+#list vs tuple
+# import time
+
+# l = list(range(10000000))
+# t = tuple(range(1000000))
+
+# start_time = time.time()
+
+# for i in l :
+#   a = i * 5 
+# print("time taken for l:",time.time()-start_time)
+  
+# start_time = time.time()
+# for j in t:
+#   b = j * 5
+# print("time taken for t:",time.time()-start_time
+
+#memory
+# import sys
+# l = list(range(1000))
+# t = tuple(range(1000))
+
+# print("Loop size:",sys.getsizeof(l))
+# print("Tuple size:",sys.getsizeof(t))
+
+#tuple revise 
+
+#special syntax - 
+# a,b,c = (10,20,30)
+# # print(a,b,c)
+# a,b = ("Asif",23,10)
+# print(a,b)
+# name,age,isStudent = ("Asif",25,True)
+# print(isStudent)
+# print(age)
+# print(name)
+# a = 1
+# b = 2 
+# a,b = b,a
+# print(a,b)
+
+#tuple tasks
+# test_list = [(5,6),(5,7),(5,8),(6,10),(7,13)]
+# new_list =[]
+# for i in test_list:
+#   for j in test_list:
+#     if i[0] == j[0]:
+#       new_list.append()
+
+# t1 = (1,2,3,0)
+# t2 = (0,1,2,3)
+
+# for i in t1:
+#   if t1[i] != t2[i]:
+    
+#   else:
+#     print(f"{t1} and {t2} are same")
+
+#question 4
+
+
+#tuple revise
+t1 = (12,23,22,11,12)
+# # print(t1)
+# print(type(t1))
+# print(t1[0])
+# t2 = ()
+# print(t2)
+# t3 = (23)
+# print(t3,type(t3))
+# t4 =(12,)
+# print(t4,type(t4))
+# t5 = ("Asif",24,True)
+# print(t5)
+# t6 = (12,3,42,("A","B"))
+# print(t6)
+# t7 = tuple("Asif")
+# print(t7)
+
+#accessing a tuple
+t1 = (10,20,"Asif",True,29.99)
+# print(t1[3])
+# print(t1[-3])
+# print(t1[len(t1)-2])
+
+# print(t1[1:4])
+# print(t1[::])
+# print(t1[::-1])
+# print(t1[:-4:-1])
+#t1[0] = 100
+# del t1[1]
+# del t1
+# print(t1)
+
+#t1[5]=30
+
+#operations on tuple
+#rithmetic - +,*
+# t1 = (12,2,23,21,"Asif")
+# t2 =(10,20,39,True)
+# print(t1+t2)
+
+# t1 =("Asif",24,True)
+# print(t1*4)
+
+t1 = (10,20,30,40)
+t2 = (10,20,30,40)
+# print(t1 > t2)
+# print(t1 == t2)
+# print(t1 is t2)
+# print(12 in t1)
+# for i in t1:
+#   print(i)
+# person = ("Asif",22,"Bangladesh")
+# name,age,country = person
+# print(f"Name:{name},Age:{age},Country:{country}")
+
+#tuple functions-len,max,min,sum,sorted
+t1 = (10,20,30,40,50,10)
+t2 = ("Asif",True,19.99)
+# print(len(t1))
+# print(len(t2))
+# print(max(t1))
+# #print(max(t2))
+# print(min(t1))
+# print(sum(t1))
+# print(sum(t2))
+#print(sorted(t1))
+#print(sorted(t2,reverse=True))
+
+# print(t1.count(10))
+#print(t1.count(100))
+# print(t1.index(100))
+numbers = (1,2,3,2,4,2,5)
+# print(numbers.count(2))
+# count = 0
+# for i in numbers:
+#   if i == 2:
+#     count +=1
+# print(count)
+# print(numbers.index(4))
+# index = -1
+# for i in numbers:
+#   if i != 4:
+#     index+=1
+# print(index)
+
+#tuple unpacking
+# t1 = (10,20,30,40)
+# name,age,num1,num2 = t1
+# print(name,age,num1,num2)
+# a,c = (1,2,3)
+# print(a,c)
+# a = 20
+# b = 40
+# b,a = a,b
+# print(a,b)
+# t = (1,2,3,4,5)
+# l 
+# t1 = tuple(l)= []
+# for i in t:
+#   l.append(i)
+# l.append(10)
+# print(l)
+# print(t1)
+  
+#tuple unpacking
+# a,b,*others = (10,20,30,40,50)
+# print(a,b,others)
+# name,age,*country =("Asif",24,"Bangladesh","India","China")
+# print(name,age,country)
+
+#zipping tuples
+# t1 = (10,20,30,40,50)
+# t2 = (100,200,300,99)
+# print(tuple(zip(t1,t2)))
+
+#data = (1,2,(3,4),(5,6,7))
+# print(data[2][1])
+# print(data[3][2])
+# for i in data:
+#   if isinstance(i,tuple):
+#     for item in i:
+#       print(item)
+#   else:
+#     print(i)
+
+#find the second largest element
+t = (10,5,20,8,15)