using System;

public class Test
{
	public static bool Func(int a, int b)
	{
		return (a -= -b) == (a += b);
	}
	
	public static void Main()
	{
		for (int a = 0; a <= 10; ++a)
	    	for (int b = 0; b <= 10; ++b)
	    		if (Func(a, b))
	    			Console.WriteLine($"{a}, {b}");
	}
}