14139 - Chess Puzzle part 1   

Description

Domo is a brilliant dog. Now he needs to solve these problems to pass the I2P.

 

In the mid2 practice, Domo has solved the N-Queens M-Rooks Problem, but now, there are some variant problems that need your help to finish.

 

Note: This problem is separated into three parts, each with different constraints. The differences between each part will be highlighted in red.


 

The first part of the chess puzzle is N-Queens M-Rooks Problem.

 

You need to find how many ways to place N queens and M rooks on an (N+M) × (N+M) chessboard such that no two of queens or rooks can attack each other in 1 step.

 

For N = 1, M = 2, there're 4 solutions:

( 0 means empty spot, Q means queen, R means rook. )

Q 0 0    0 R 0
0 0 R    R 0 0
0 R 0    0 0 Q

0 R 0    0 0 Q
0 0 R    R 0 0
Q 0 0    0 R 0

 

Possible move of Queen:

Possible move of Rook:

 

Input

The first line consists of an integer T (1 ≤ T ≤ 10) indicating the number of test cases.

 

For the next T lines, each line consists of two integer N and M (1 ≤ N, M ≤ 9, 1 ≤ N+M ≤ 9)

 

Output

For each test case, output the number of ways that you can place chesses.

 

Sample Input  Download

Sample Output  Download

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