mencari bilangan prima

#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;
}