find20primes.c

#include <stdio.h>
#include <stdlib.h>
main (){
    int j;
    int primecnt;
    int primes[20];
    primecnt=1;
    primes[0]=2;
    int cand=3;
    while (primecnt < 20){
        for (j=0; j<primecnt; j++){
            if (cand % primes[j] == 0){
                goto notprime;
            }
        }
        primes[primecnt]=cand;
        primecnt += 1;
      notprime:
        cand += 2;

    }
    for (j=0; j<primecnt; j++){
        printf("%d\n", primes[j]);
    }
    exit(0);
}