これはどう？
#include <stdio.h>
#define YES 1
#define NO 0
#define MAX 10000
#define BOXNUM 100 /* BOXNUM= MAX/100 */

int isprime(int n);

main()
{
int i, j, k;

int box[BOXNUM];
for (j = 0; j < BOXNUM ; j++) box[j] = 0;

printf("2 "); /* 2 is prime */
box[0] = 1;

for (i = 3; i < MAX; i = i + 2) { /* check only odd numbers */
if (isprime(i) == YES){
printf("%d ", i);
box[i/100]++;
}
}
printf("End.\n");

for (k = 0; k < BOXNUM; k++)
printf("box%d: %d\n", k, box[k]);
}

/* n is prime? */
int isprime(int n)
{
int i;

for (i = 3; i < n; i = i+2){ /* devide n by odd number < n */
if (n % i == 0) return NO;
}
return YES;
}