C Exercises: Count the number of vowels in a given string using an inline function

C inline function: Exercise-7 with Solution

Write a C program to count the number of vowels in a given string using an inline function.

Sample Solution:

C Code:

#include <stdio.h>

#include <ctype.h>

inline int count_vowels(const char * str) {
  int ctr = 0;
  while ( * str != '\0') {
    char ch = tolower( * str);
    if (ch == 'a' || ch == 'e' || ch == 'i' || ch == 'o' || ch == 'u') {
      ctr++;
    }
    str++;
  }
  return ctr;
}
int main() {
  char str[] = "w3resource.com";
  int vowels = count_vowels(str);
  printf("The string \"%s\" contains %d vowels.\n", str, vowels);
  char str1[] = "United States of America ";
  vowels = count_vowels(str1);
  printf("\nThe string \"%s\" contains %d vowels.\n", str1, vowels);
  return 0;
}

Sample Output:

The string "w3resource.com" contains 5 vowels.

The string "United States of America " contains 10 vowels.

Explanation:

The above count_vowels() function uses a while loop to iterate over each character in the string. It converts each character to lowercase using the tolower() function and then checks if it is a vowel (i.e., 'a', 'e', 'i', 'o', or 'u'). If the character is a vowel, it increments a counter variable. Finally, the function returns the total count of vowels in the string.

In the main() function, we declare a test string, call the count_vowels() function on it, and print the result.

Flowchart:

C Programming Code Editor:

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