private static void init() {
		D = new int[][]{{0, 10, 20, 30, 40, 50}, 
					{12, 0, 18, 30, 25, 21},
					{23, 19, 0, 5, 10, 15},
					{34, 32, 4, 0, 8, 16},
					{45, 27, 11, 10, 0, 18}, 
					{56, 22, 16, 20, 12, 0}
					};
	}