problema 374

#include <iostream>
using namespace std;
int main()
{
    int n,d=2,ok=0,a=2;
    cin>>n;
    while (a<=n){
    d=2;
    ok=0;
    while (d<=a/2){
        if (a%d==0)
            ok=1;
    d++;
    }
    if (ok==0)
        cout<<a<<" ";
    a++;
    }
}