2259：Continuous Same Game (2)

After repeated attempts, LL finds the greedy strategy is very awful in practice. Even there is no apparent evidence to proof it is better than a random one. So he has to drop this strategy and try to discover a better one.

There are 100 test cases. Each test case begins with two integers n,m ( 5<=n,m<=20 ), which is the size of the board. Then n lines follow, each contains m characters, indicating the color of the block. There are 5 colors, and each with equal probability.

For each test case, first output a single line containing the number of steps S. Then S lines follow, each contains two integers indicating the position of an arbitrary block of the group you want to remove.

For the i-th test case, let Ai is the total point of your scheme and Bi is the total point of the greedy strategy . Then I will calculate the average of (Ai/Bi), 1<=i<=100. You will get WA if your ouput is invalid or this average is less than 1.5.