答案（求赞！！！！！！！）

#include<iostream>
using namespace std;
int main()
{
	int n;
    cin>>n;
    if(n%3==0)
        cout<<"3"<<" ";
	if(n%5==0)
        cout<<"5"<<" ";
	if(n%7==0)
        cout<<"7"<<" ";
    if(n%3!=0&&n%5!=0&&n%7!=0)
        cout<<"n";
}