测试结果：

Subtask #0

1. 3ms/680.00KB AC
2. 3ms/684.00KB AC
3. 3ms/684.00KB AC
4. 3ms/684.00KB AC
5. 3ms/684.00KB AC
6. 3ms/680.00KB AC
7. 1.20s/684.00KB TLE
8. 1.20s/684.00KB TLE
9. 1.20s/680.00KB TLE
10. 1.20s/696.00KB TLE

Subtask #1

11. 1.20s/692.00KB TLE
12. 1.20s/684.00KB TLE
13. 1.20s/688.00KB TLE
14. 1.20s/676.00KB TLE
15. 1.20s/684.00KB TLE

#include <bits/stdc++.h>
using namespace std;
int a,b,d;
bool is_prime(int x){
	bool flag=true;
	for(int i=2;i<=(sqrt(sqrt(sqrt(x))));i++){
		if(b==2){
			flag=true;
			break;
		}
		else{
		if(x%i==0){
			flag=false;
			break;
		}
		else{
			b++;
		}
	}
	}
	return flag;
}
int main(){
cin>>a;
for(int c=1;c<a;c++){
	if(a%c==0&&is_prime(c)){
        	d=c;
	}
}
cout<<d;
  return 0;
}