Here is a code to see if a number is prime
Code:#include <stdio.h>
int main() {
int N, a, b;
printf("What number do you want to test?\n");
scanf("%d",&N);
for(a=2; a<N; a++) {
if(N % a == 0) {
printf("%d is divisble by %d.\n", N, a);
break;
}
}
if(a == N) //the loop ran completely and never 'broke'
printf("%d is a prime!\n",N);
return 0;