TouchStone
  Please Login
Login Sign Up
 Homepage  Problem Set  Examinations  Submissions  Discussions  Statistics
  • Home
  • Problem Set
  • P4464
  • Problem
  • P4464Color the chessboard
    Limits : Time Limit : 1000 MS   Memory Limit : 565536 KB
    Description

    There is a chessboard with n rows and m columns, at first every position is colored red or blue or white. HazelFan want to change the color of every white position into red one or blue one, so that every rectangle in the chessboard with even rows and even colums, contains same number of red positions and blue positions. HazelFan wants to know how many ways are there to color the chessboard, module 998244353.

    Input Format

    The first line contains a positive integer T(1≤T≤5), denoting the number of test cases.
    For each test case:
    The first line contains two positive integers n,m(1≤n,m≤10^3).
    The next n lines, the ith line contains a string of length m, the jth character describes the position in the ith row and the jth column as below:
    'R': the position is colored red.
    'B': the position is colored blue.
    '?': the position is colored white.

    Output Format

    For each test case:
    A single line contains a nonnegative integer, denoting the answer.

    Sample Input

    2
    2 2
    RB
    ??
    3 3
    ???
    ?R?
    ???

    Sample Output

    2
    7