Python program to count the number of vowels using set in a given string

In this program, given a user input string. We have to count number of vowels in this string. Here we use set in Python. Set is an unordered collection data type that is iterable, mutable and no duplicate elements.

Example

Input : str1=pythonprogram
Output : 3

Algorithm

Step 1: First we use one counter variable which is used to count the vowels in the string.
Step 2: Creating a set of vowels.
Step 3: Then traverse every alphabet in the given string.
Step 4: If the alphabet is present in the vowel set then counter incremented by 1.
Step 5: After the completion of traversing print counter variable.

Example Code

# Program to count vowel in  
# a string using set 
   
def countvowel(str1): 
   c = 0
   # Creating a set of vowels
   s="aeiouAEIOU"
   v = set(s) 

   # Loop to traverse the alphabet 
   # in the given string 
   for alpha in str1: 
      # If alphabet is present 
      # in set vowel 
      if alpha in v: 
         c = c + 1
   print("No. of vowels ::>", c) 

# Driver code  
str1 = input("Enter the string ::>") 
countvowel(str1) 

Output

Enter the string ::> pythonprogram
No. of vowels ::> 3