class Solution(object):

def subarraySum(self, nums, k):

"""

:type nums: List[int]

:type k: int

:rtype: int

"""

"""

# Not quite working - something wrong

# Brute force solution

n = len(nums)

result = []

for j in range(0,n):

for i in range(n):

if nums[i] == k:

print nums[i]

result.append(nums[i])

if i+j <= n and sum(nums[i:i+j]) == k:

print nums[i:i+j]

result.append(nums[i:i+j])

return len(result)

"""

"""

# Running Sum Technique - 100pass

# Variable to calculate the sum as we progress through the array

sumi = 0

# Hashmap to maintain the sum data and respective counts

hashmap = {}

# Variable to hold the result

result = 0

for i in nums:

# Running sum calculation as we progress through the array

sumi += i

#

result += hashmap.get(sumi-k,0) + (1 if sumi == k else 0)

# Update the sum entry present in the hashmap

hashmap[sumi] = hashmap.get(sumi,0) + 1

return result

"""

# 100 pass - Running Sum technique and minus k to find its exitence and increase count

# As we progress through the array finding the sums => sum(a[5]) - k = sum(a[2]) which provides sum(3,4)

sumi = 0

# A dictionary to count the entries as values and respective entries as key

hashmap = collections.Counter()

result = 0

# For 0 length

hashmap[0] += 1

n = len(nums)

for i in range(n):

sumi += nums[i]

if sumi-k in hashmap:

result += hashmap[sumi-k]

hashmap[sumi] += 1

return result