Find the highest frequency character in a string with C.

#include <stdio.h>

int main()
{
    char str[100];
    int freq[200]; // Store frequency of each character
    int i = 0, max;
    int ascii;

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

    /* Initializes frequency of all characters to 0 */
    for (i = 0; i < 200; i++)
    {
        freq[i] = 0;
    }

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

        i++;
    }

    /* Finds maximum frequency */
    max = 0;
    for (i = 0; i < 200; i++)
    {
        if (freq[i] > freq[max])
            max = i;
    }

    printf("Maximum occurring character is '%c' = %d times.", max, freq[max]);

    return 0;
}

Output

Enter any string : Learn With Rezaul Karim
Maximum occurring character is ' ' = 3 times.