Given a n*n matrix, find the maximum length path (starting from any cell) such that all cells along the path are in increasing order with a difference of 1.

We can move in 4 directions from a given cell (i, j), i.e., we can move to (i+1, j) or (i, j+1) or (i-1, j) or (i, j-1) with the condition that the adjacent cells have a difference of 1.

Input:
The first line of input contains an integer T denoting the number of test cases. Then T test cases follow. Each test case contains an integer n denoting the size of the nxn matrix. The following lines contain the nxn matrix. 

Output:
Print the length of the longest path.

Constraints:
1<=T<=100
1<=n<=50
1<=arr[i][j]<=50

Example:
Input:
2
3
1 2 9 5 3 8 4 6 7
4
1 7 8 9 2 11 12 17 3 15 14 13 4 5 25 30

Output:
4
5