Minimum Watering Operations

Given a rectangular farm with n rows and m columns, each cell is either empty (represented by '.') or contains a crop (represented by '*'). A single watering operation waters a contiguous group of crops. Two cells are considered adjacent if they share a common edge. Formally, two cells \( (i, j) \) and \( (k, l) \) are adjacent if \( |i-k| + |j-l| = 1 \).

Your task is to determine the minimum number of watering operations required to water all crops in the farm.

inputFormat

The input is read from stdin and follows this format:

• The first line contains an integer \( T \), the number of test cases.
• For each test case, the first line contains two integers \( n \) and \( m \) – the number of rows and columns.
• This is followed by \( n \) lines, each containing a string of length \( m \) representing the farm grid.

outputFormat

For each test case, output a single integer on a new line representing the minimum number of watering operations required to water all crops. The output should be written to stdout.

## sample

2
3 4
.*..
..*.
....
2 3
*..
..*

2
2

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