C Program to Find the Frequency of Characters in a String

This program asks user to enter a string and a character and checks how many times the character is repeated in the string.

To understand this example, you should have the knowledge of following C programming topics:

Example: Find the Frequency of Characters

#include <stdio.h>

int main()
{
   char str[1000], ch;
   int i, frequency = 0;

   printf("Enter a string: ");
   gets(str);

   printf("Enter a character to find the frequency: ");
   scanf("%c",&ch);

   for(i = 0; str[i] != '\0'; ++i)
   {
       if(ch == str[i])
           ++frequency;
   }

   printf("Frequency of %c = %d", ch, frequency);

   return 0;
}

Output

Enter a string: This website is awesome.
Enter a character to find the frequency: e
Frequency of e = 4

In this program, the string entered by the user is stored in variable str.

Then, the user is asked to enter the character whose frequency is to be found. This is stored in variable ch.

Now, using the for loop, each character in the string is checked for the entered character.

If, the character is found, the frequency is increased. If not, the loop continues.

Finally, the frequency is printed.