Python | Count vowels in a string

Program:

# count vowels in a string 

# declare, assign string 
str = "Hello world"

# declare count 
count = 0

# iterate and check each character
for i in str:
	# check the conditions for vowels
	if( i=='A' or i=='a' or i=='E' or i=='e'
	or i=='I' or i=='i' or i=='O' or i=='o'
	or i=='U' or i=='u'):
		count +=1;
		
# print count
print "Total vowels are: ", count

Output

    Total vowels are:  3

Implement the program by creating functions to check vowel and to count vowels:

Here, we are creating two functions:

1) isVowel()

This function will take character as an argument, and returns True, if character is vowel.

2) countVowels()

This function will take string as an argument, and return total number of vowels of the string.

Program:

# count vowels in a string 

# function to check character
# is vowel or not 
def isVowel(ch):
    # check the conditions for vowels 
	if(ch=='A' or ch=='a' or ch=='E' or ch=='e'
	or ch=='I' or ch=='i' or ch=='O' or ch=='o'
	or ch=='U' or ch=='u'):
		return True
	else:
		return False

# function to return total number of vowels
def countVowel(s) :
	# declare count 
	count =0
	# iterate and check characters
	for i in str:
		if(isVowel(i) == True):
			count += 1 
	return count
	
# Main code 
# declare, assign string
str = "Hello world"

# print count 
print "Total vowels are: ", countVowel(str)

Output

    Total vowels are:  3