C. Cornerstime limit per test1 secondmemory limit per test256 megabytesinputstandard inputoutputstandard outputYou 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.InputThe 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.OutputFor each test case output the maximum number of operations you can do with the given matrix.ExampleInput
44 31011110111103 41110011101112 200002 21111Output
8
9
0
2
NoteIn 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.
44 31011110111103 41110011101112 200002 21111
8 9 0 2 
['greedy', 'implementation', '*1200']