OR-postavke2-zad3

#include<stdio.h>
#include<math.h>

int Fja (int *niz,int vel) {
   int i, max_prost=0, min_prost=10000, j, prost=1,br_prostih=0;
   for (i=0; i<vel; i++) {
        for (j=2; j<niz[i]; j++)
        {  if (niz[i]%j==0)
            prost=0;
        }
        if (prost==1) {
                br_prostih++;
                if (niz[i]>max_prost) max_prost=niz[i];
                else if (niz[i]<min_prost) min_prost=niz[i];
        }

   }
   if (br_prostih==0) return -1;
   return max_prost-min_prost;
}
int main () {
    int niz[5]={13,3,4,6,8};
    printf("%d",Fja(niz,5));
    return 0;
}