Trapping Rain Water II Problem Statement

Given an M * N matrix where each cell's value represents its height in a 2-D elevation map, calculate the total volume of water that can be trapped after rainfall.

Input:

The first line contains an integer ‘T’ representing the number of test cases.
For each test case:
 - The first line contains two integers 'M' and 'N', indicating the number of rows and columns respectively.
 - The following 'M' lines, each containing 'N' space-separated integers, denote the height of each cell in the matrix.

Output:

For each test case, output a single integer representing the volume of water that can be trapped.
Print each result on a new line.

Example:

Input:
1
3 3
5 5 5
5 2 3
6 9 8
Output:
1

Explanation:

The given matrix forms a 2-D elevation map where, after rain, water is trapped leading to a total volume of 1 unit.

Constraints:

• 1 <= T <= 10
• 1 <= M,N <= 100
• 1 <= matrix[i][j] <= 10^3

Note: You aren’t required to handle the printing of results; this is managed elsewhere. Your task is to implement the function to determine the trapped volume.