[[0, 0], [1, 0], [5, 0], [9, 0], [0, 1], [3, 1], [5, 1], [6, 1], [8, 1], [3, 2], [4, 2], [6, 2], [9, 2], [0, 3], [4, 3], [5, 3], [7, 3], [0, 4], [1, 4], [2, 4], [4, 4], [6, 4], [8, 4], [1, 5], [3, 5], [5, 5], [7, 5], [8, 5], [0, 6], [3, 6], [5, 6], [1, 7], [3, 7], [4, 7], [5, 7], [9, 7], [0, 8], [1, 8], [3, 8], [2, 9], [6, 9], [7, 9], [9, 9]]
4