Day 74 : Python Program to Count the Number of Vowels in a String

 

def count_vowels(input_string):

    vowels = "aeiouAEIOU"

    count = 0

    for char in input_string:

        if char in vowels:

            count += 1

    return count

user_input = input("Enter a string: ")

vowel_count = count_vowels(user_input)

print(f"The number of vowels in the string is: {vowel_count}")

#source code --> clcoding.com

Code Explanation:

def count_vowels(input_string):

def: This keyword defines a function in Python.

count_vowels: The name of the function.

input_string: A parameter representing the string passed to the function when called.

    vowels = "aeiouAEIOU"

vowels: A string containing all vowel characters (both lowercase and uppercase: 'a', 'e', 'i', 'o', 'u' and 'A', 'E', 'I', 'O', 'U').

This list of vowels will be used to check if a character is a vowel.

    count = 0

Initializes a variable count to 0. This variable will store the number of vowels found in the input string.

    for char in input_string:

for: A loop that iterates over each character in the input_string.

char: A temporary variable that represents the current character being processed in the string.

        if char in vowels:

if: A conditional statement that checks whether the current character (char) is present in the vowels string.

char in vowels: Returns True if the character is found in the vowels string, indicating that it is a vowel.

            count += 1

If the condition (char in vowels) is True, this line increments the count variable by 1. This tracks the total number of vowels encountered.

    return count

After the loop finishes processing all characters, this line returns the total value of count (the number of vowels) to the caller of the function.

user_input = input("Enter a string: ")

input(): Prompts the user to type a string into the program. It displays the message "Enter a string: " and waits for the user to input a value.

user_input: A variable that stores the string entered by the user.

vowel_count = count_vowels(user_input)

Calls the function count_vowels, passing the user-provided string (user_input) as an argument.

The function processes the string and returns the count of vowels.

The result is stored in the variable vowel_count.

print(f"The number of vowels in the string is: {vowel_count}")

print(): Outputs the specified message to the console.

f-string: A formatted string (introduced in Python 3.6) that allows embedding variables directly inside curly braces {}.

Displays the message along with the value of vowel_count.