#include <iostream>
#include <fstream>
#include <string>

using namespace std;

int main() {
	ofstream myfile;
	myfile.open("voffi.txt");

	for (int a = 1; a < 501; a++)
	{
		myfile << "person(" + to_string(a) + ").\n";
	}

	for (int a = 1; a < 501; a++)
	{
		for (int b = a + 1; b < 501; b++)
		{
			myfile << "knows(" + to_string(a) + "," + to_string(b) + ").\n";
		}
	}

	myfile.close();
	return 0;
}