Autonomous Vehicles Navigation

You are given a grid-based map representing a city divided into cells. Each cell is either free (denoted by '.') or blocked by an obstacle (denoted by '#'). For each test case, you are provided with the dimensions of the grid, the grid itself, and the starting and ending positions. Your task is to determine whether there is a valid path from the start to the destination by moving in four directions (up, down, left, right) without visiting blocked cells. Note that the positions are provided in 1-indexed format.

Formally, given a grid of size \( M \times N \) and start point \( (S_r, S_c) \) and end point \( (E_r, E_c) \), determine if there exists a path such that each move is to an adjacent cell and the cell contains a '.' character. Output YES if a path exists, otherwise NO.

inputFormat

The input is read from stdin and has the following format:

T
M N
row1
row2
... (M rows in total)
S_r S_c E_r E_c
(repeated T times)

Where:

• T is the number of test cases.
• M and N denote the number of rows and columns in the grid.
• Each of the next M lines contains a string of length N consisting of '.' and '#' characters.
• The final line of each test case contains four integers: the starting row, starting column, ending row, and ending column (all 1-indexed).
</p>

outputFormat

The output should be written to stdout. For each test case, output a single line containing either YES if a valid path exists, or NO otherwise.

## sample

1
3 4
....
..#.
....
1 1 3 4

YES