AC代码，放心使用

#include <bits/stdc++.h>
using namespace std;
int n;
int zs(int a)
{
	for (int i = 2; i < a; i += 1)
	{
		if (a % i == 0)
		{
			return 0;
		}
	}
	return 1;
}
int main()
{
	cin >> n;
	for (int i = 2; i <= sqrt(n); i += 1)
	{
		if ((zs(i)) && (zs(n / i)))
		{
			if (n % i == 0)
			{
				cout << "It's a Tongtong number." << endl;
				return 0;	
			}
		}
	}
	cout << "It's not a Tongtong number." << endl;
	return 0;
}

#include <bits/stdc++.h> int prime ( int a ) ; using namespace std ; int main ( ) { int z , n ; cin >> n ; if ( prime ( n ) == true || n == 1 ) { cout << "It's not a Tongtong number." ; return 0 ; } for ( int i = 2 ; i <= n / 2 ; i++ ) { z = i ; if ( prime ( z ) == true ) { if ( n % z == 0 && prime ( n / z ) == true ) { cout << "It's a Tongtong number." ; return 0 ; } else if ( n % z == 0 && prime ( n / z ) == false ) { cout << "It's not a Tongtong number." ; return 0 ; } } } cout << "It's not a Tongtong number." ; } int prime ( int a ) { bool flag = true ; if ( a == 1 ) { flag = false ; } for ( int i = 2 ; i * i <= a ; i++ ) { if ( a % i == 0 ) { flag = false ; break ; } } return flag ; }

#include <bits/stdc++.h> using namespace std; int n; int zs(int a) { for (int i = 2; i < a; i += 1) { if (a % i == 0) { return 0; } } return 1; } int main() { cin >> n; for (int i = 2; i <= sqrt(n); i += 1) { if ((zs(i)) && (zs(n / i))) { if (n % i == 0) { cout << "It's a Tongtong number." << endl; return 0; } } } cout << "It's not a Tongtong number." << endl; return 0; }