/* Count uppercase letters in a file. */

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

int main(int argc, char *argv[])
{
   int    c, i, letter[26];
   FILE   *ifp, *ofp;

   if (argc != 3) {
      printf("\n%s%s%s\n\n%s\n%s\n\n",
         "Usage:  ", argv[0], "  infile  outfile",
         "The uppercase letters in infile will be counted.",
         "The results will be written in outfile.");
      exit(1);
   }
   ifp = fopen(argv[1], "r");
   ofp = fopen(argv[2], "w");
   for (i = 0; i < 26; ++i)       /* initialize array to zero */
      letter[i] = 0;
   while ((c = getc(ifp)) != EOF) 
      if (c >= 'A' && c <= 'Z')     /* find uppercase letters */
         ++letter[c - 'A'];
   for (i = 0; i < 26; ++i) {                /* print results */
      if (i % 6 == 0)
         putc('\n', ofp);
      fprintf(ofp, "%c:%5d     ", 'A' + i, letter[i]);
   }
   putc('\n', ofp);
   return 0;
}