B'You are playing one famous sandbox game with the three-dimensional world. The map of the world can be represented as a matrix of size n x m , where the height of the cell (i, j) is a_{i, j} . You are in the cell (1, 1) right now and want to get in the cell (n, m) . You can move only down (from the cell (i, j) to the cell (i + 1, j) ) or right (from the cell (i, j) to the cell (i, j + 1) ). There is an additional restriction: if the height of the current cell is x then you can move only to the cell with height x+1 . Before the first move you can perform several operations. During one operation, you can decrease the height of any cell by one. I.e. you choose some cell (i, j) and assign (set) a_{i, j} := a_{i, j} - 1 . Note that you can make heights less than or equal to zero. Also note that you can decrease the height of the cell (1, 1) . Your task is to find the minimum number of operations you have to perform to obtain at least one suitable path from the cell (1, 1) to the cell (n, m) . It is guaranteed that the answer exists. You have to answer t independent test cases. The first line of the input contains one integer t ( 1 <= t <= 100 ) -- the number of test cases. Then t test cases follow. The first line of the test case contains two integers n and m ( 1 <= n, m <= 100 ) -- the number of rows and the number of columns in the map of the world. The next n lines contain m integers each, where the j -th integer in the i -th line is a_{i, j} ( 1 <= a_{i, j} <= 10^{15} ) -- the height of the cell (i, j) . It is guaranteed that the sum of n (as well as the sum of m ) over all test cases does not exceed 100 ( sum n <= 100; sum m <= 100 ). For each test case, print the answer -- the minimum number of operations you have to perform to obtain at least one suitable p'...