count.c

#include <stdio.h>

/* count digits, whitespace, others */

int main(void)
{
  int c, i, nwhite, nother;
  int ndigit[10];

  nwhite = nother = 0;

  /* Initialize array to zeroes */
  for (i=0; i < 10; ++i) {
    ndigit[i] = 0;
  }

  while ((c = getchar()) != EOF) {
    if (c >= '0' && c <= '9') {
      ++ndigit[c-'0'];
    }
    else if (c == ' ' || c == '\n' || c == '\t') {
      ++nwhite;
    }
    else ++nother;
  }

  printf("digits =");
  for (i=0; i< 10; ++i) {
    printf(" %d", ndigit[i]);
  }
  printf(", white space = %d, other = %d\n", nwhite, nother);

  return 0;
}