Bilangan Prima {Strategi Algoritma}

#include <cstdlib>
#include <iostream>
#include <math.h>

using namespace std;
bool Prima (int x){
     int k, y;
     bool test;
   
     if (x<2){
              return false;
     }else if (x==2){
            return true;
     } else {
            y = ceil(sqrt(x));
            test = true;
            }
   
     while (test && (y>=2)){
           if (x % y == 0){
                 test = false;
           } else {
                  y = y-1;
           }
           }
         
           return test;
           }
int main(int argc, char *argv[])
{
    int x;
    cout<<"masukkan nilai:"<<endl;
    cin>>x;
    cout<<"Prima:"<<Prima(x)<<endl;
  
    system("PAUSE");
    return EXIT_SUCCESS;
}