'''

Question :

Given a string consisting of English alphabets, the task is to count the number of adjacent pairs of vowels.

For example :

Input: str = “abaebio”

Output: 2

(a, e) and (i, o) are the only valid pairs.

Source:A very Common Interview Question.

Time Complexity : The goal is to complete this question in O(n).

'''

#function to check whether a character is vowel or not

def is_vowel(character):

if character.lower() in ['a', 'e', 'i', 'o', 'u']:

return True

else:

return False

#function to find the number of adjacent vowel pairs.

def adjacent_pairs(string):

string=string.lower()

n=len(string)

count = 0

for i in range(0,n):

if ((is_vowel(string[i]) and is_vowel(string[i + 1]))):

count += 1

return count

#driver code

string=input("enter string")

print (adjacent_pairs(string),"is the number of adjacent pairs of vowels")