#include <stdio.h> #include <cmath> int prime(int a){ a = abs(a); if (a == 1 || a == 0) return false; int divider = 2; while(divider <= (a / 2 + 1) && divider != a){ if (a % divider == 0) return false; divider++; } return true; } int main(void) { int a = -7; printf("Num %d %s\n", a,prime(a) ? "is prime": "is not prime"); return 0; }