Python Program to Count Number of Vowels in a String using Sets

This Python program uses sets to count the number of vowels in a given string.

Problem Statement:

You are tasked with writing a Python program that takes a string as input and counts the number of vowels (both uppercase and lowercase) present in the string using sets.

Python Program to Count Number of Vowels in a String using Sets

def count_vowels(input_string):
    vowels = {'a', 'e', 'i', 'o', 'u', 'A', 'E', 'I', 'O', 'U'}
    vowel_count = 0

    for char in input_string:
        if char in vowels:
            vowel_count += 1

    return vowel_count

# Input from the user
user_input = input("Enter a string: ")
result = count_vowels(user_input)
print("Number of vowels:", result)

How it Works:

1. The program defines a function count_vowels that takes an input string as its parameter.
2. A set named vowels is created containing all lowercase and uppercase vowels.
3. The program iterates through each character in the input string using a for loop.
4. If the current character is found in the vowels set, the vowel_count is incremented by 1.
5. After iterating through all characters, the vowel_count is returned.
6. The user is prompted to enter a string.
7. The count_vowels function is called with the user-input string, and the result is printed as the number of vowels in the string.

Input/Output: