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Do you know Minesweeper, the famous video game? The player is initially
presented with a grid of undifferentiated squares. Some randomly selected
squares, unknown to the player, are designated to contain mines. One square
can contain at most one mine.
The game is played by revealing squares of the grid, typically by clicking
them. After that, a digit is revealed in the square, indicating the number of
adjacent squares (under 8-way connectivity, that is, if two squares share
either an edge or a corner, they are considered adjacent) that contain mines.
If this number is zero then the surrounding squares are automatically also
revealed. This process applies recursively and automatically every time a new
square with count zero is revealed.
Now, given a Minesweeper situation, you need to check if it is possible that
such a situation can occur after **exactly** 1 click on the grid. Note that
the game is designed in such a way, that the first clicked square never
contains a mine.
## Input:
The first line contains a single integer **T**, **T** ≤ 20.
Then **T** test cases follow.
The first line of each test case contains two integers **n**, **m** which
indicate the size of the grid (**1 ≤ n ≤ 16, 1 ≤ m ≤ 32**).
**n** lines follow, each line contains **m** characters describing the situation of the grid.
The meaning of the characters are as follows:
x: the square is not revealed after the first click
0 - 8: the number of mines that are adjacent to this square
## Output:
Output a single line containing 'Yes' if the situation is valid after 1 click,
and 'No' otherwise (quotes for clarity).
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