# Solution Exercise 21: algorithm python that determines the number of vowels in given string

Mar 9, 2023

#### Exercise 21

Write a simple Python program that counts the number of vowels in a given string. Example: for the string s = 'anticonstitutionally' the program must return the following message: The string anconstitutionally has 9 vowels.

#### Solution

```s = 'anticonstitutionally'
vowels = 'aeiou'
count = 0

for letter in s:
if letter in vowels:
count += 1

print(f"The string {s} has {count} vowels.")
"""
When you run this program with the string 'anticonstitutionally',
it will output:
The string anticonstitutionally has 9 vowels.
"""```

In this program:

1. we define the input string s and a string vowels: that contains all the vowel letters.
2. We also initialize a variable count to 0: which will keep track of the number of vowels in the string.
3. We then use the for loop: to iterate through each letter in the input string s, and check if the letter is a vowel by using the in operator to check if it's in the vowels string.
4. If the letter is a vowel: we increment the count variable by 1.
5. Finally: we print out a message using an f-string that displays the original string s and the number of vowels that were found in it.

Younes Derfoufi
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