Problem C

Statement
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Description:
You are given a matrix consisting of $$$n$$$ rows and $$$m$$$ columns. Each cell of this matrix contains $$$0$$$ or $$$1$$$.

Let's call a square of size $$$2 \times 2$$$ without one corner cell an L-shape figure. In one operation you can take one L-shape figure, with at least one cell containing $$$1$$$ and replace all numbers in it with zeroes.

Find the maximum number of operations that you can do with the given matrix.

Input Format:
The first line contains one integer $$$t$$$ ($$$1 \leq t \leq 500$$$) — the number of test cases. Then follow the descriptions of each test case.

The first line of each test case contains two integers $$$n$$$ and $$$m$$$ ($$$2 \leq n, m \leq 500$$$) — the size of the matrix.

Each of the following $$$n$$$ lines contains a binary string of length $$$m$$$ — the description of the matrix.

It is guaranteed that the sum of $$$n$$$ and the sum of $$$m$$$ over all test cases does not exceed $$$1000$$$.

Output Format:
For each test case output the maximum number of operations you can do with the given matrix.

Note:
In the first testcase one of the optimal sequences of operations is the following (bold font shows l-shape figure on which operation was performed):

- Matrix before any operation was performed:  101111011110
- Matrix after $$$1$$$ operation was performed:  100101011110
- Matrix after $$$2$$$ operations were performed:  100100011110
- Matrix after $$$3$$$ operations were performed:  100100010110
- Matrix after $$$4$$$ operations were performed:  100000010110
- Matrix after $$$5$$$ operations were performed:  100000010100
- Matrix after $$$6$$$ operations were performed:  100000000100
- Matrix after $$$7$$$ operations were performed:  000000000100
- Matrix after $$$8$$$ operations were performed:  000000000000

In the third testcase from the sample we can not perform any operation because the matrix doesn't contain any ones.

In the fourth testcase it does not matter which L-shape figure we pick in our first operation. We will always be left with single one. So we will perform $$$2$$$ operations.

Evaluations

Eval IDRun IDProviderModelLangSuccessTimestampPromptResponseStdoutStderrRetry
7 20260124-045845 vertex gemini-3-pro-preview go true 2026-01-24T05:04:11.24348Z View View View View Retry