Write a program to print a histogram of the frequencies of different characters in its input.

#include <stdio.h>
#include <ctype.h>

#define    MAXHIST     15          /* max length of histogram */
#define    MAXCHAR      128        /*max different characters */

/*print horizontal histogram freq. of different characters */
int main(){
    int c, i;
    int len;                         /* length of each bar */
    int maxvalue;                    /* maximum value for cc[] */
    int cc[MAXCHAR];                 /* character counters */

    for (i=0 ;i <MAXCHAR; ++i)
           cc[i] = 0;
    while ((c =getchar()) != EOF)
        if (c < MAXCHAR)
               ++cc[c];
    maxvalue = 0;
   for( i = 1; i < MAXCHAR; ++i){
       if(isprint(i))
           printf(" %5d - %c - %5d : ", i, i, cc[i]);
       else
          printf(%5d -  - %5d : ", i, cc[i])
      if (cc[i] > 0){
             if ((len = cc[i] * MAXHIST / maxvalue) <= 0)
                   len = 1;
       }else
            len = 0;
       while (len > 0){
              putchar(' *');
              --len;
       }
        putchar('\n');
   }
}