题解
1 1 1 1 1 1 1 1 2 X 1 X 1 2 1 X 0 1 1 X 2 1 1 1 M 1 1 3 1 X 1 1 2 X 3 1 1 X 1 X 0 3 1 2 2 3 3 3 6