C Programming: Find maximum occurring character in a string

C String: Exercise-10 with Solution

Write a program in C to find maximum occurring character in a string.

Sample Solution:

C Code:

#include <stdio.h>
#include <string.h>
#include <stdlib.h>

#define str_size 100 //Declare the maximum size of the string
#define chr_no 255 //Maximum number of characters to be allowed

void main()
{
    char str[str_size];
	int ch_fre[chr_no];
    int i = 0, max;
    int ascii;
	
       printf("\n\nFind maximum occurring character in a string :\n");
       printf("--------------------------------------------------\n"); 	
       printf("Input the string : ");
       fgets(str, sizeof str, stdin);


    for(i=0; i<chr_no; i++)  //Set frequency of all characters to 0
    {
        ch_fre[i] = 0;
    }


    /* Read for frequency of each characters */
    i=0;
    while(str[i] != '\0')
    {
        ascii = (int)str[i];
        ch_fre[ascii] += 1;

        i++;
    }

    max = 0;
    for(i=0; i<chr_no; i++)
    {
        if(i!=32)
        {
        if(ch_fre[i] > ch_fre[max])
            max = i;
        }
    }	
    printf("The Highest frequency of character '%c' appears number of times : %d \n\n", max, ch_fre[max]);
}

Sample Output:

Find maximum occurring character in a string :                                                                
--------------------------------------------------                                                            
Input the string : Welcome to w3resource                                                                      
The Highest frequency of character 'e' appears number of times : 4 

Flowchart:

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