View difference between Paste ID: G92H7k78 and

-
+#include <stdio.h>
 #include <stdlib.h>
 
 #define MAX 1000
 
 int prevprime[MAX];
 
 int isprime(int n) {
     int i;
     if (n < 2) return 0;
     for(i = 2; i*i <= n; i++) {
         if (n % i == 0) return 0;
     }
     return 1;
 }
 void init_prevprime() {
     int i;
     prevprime[0] = -1;
     for(i = 1; i < MAX; i++) {
         prevprime[i] = isprime(i-1) ? i-1 : prevprime[i-1];
     }
 }
 void findsums(int n) {
     int seq[MAX/2];
     int nseq = 0;
     int p = prevprime[n+1];
     int nsols = 0;
     int i;
     for(;;) {
         n -= p;
         seq[nseq++] = p;
         if (n == 0) {
             printf("%d:",++nsols);
             for(i = 0; i < nseq; i++) {
                 printf(" %d", seq[i]);
             }
             putchar('\n');
         }
         if (n <= 0) {
             p = -1;
         }
         while (p < 0 && nseq > 0) {
             p = seq[--nseq];
             n += p;
             p = prevprime[p];
         }
         if (p < 0 && nseq <= 0) {
             break;
         }
     }
     printf("Total %d sums for %d\n", nsols, n);
 }
 
 int main(int argc, char **argv) {
     (void)argc;
     init_prevprime();
     while(argv[1]) {
         int n = atoi(argv[1]);
         printf("Sums for %d:\n", n);
         findsums(n);
         argv++;
     }
     return 0;
 }