Once N boys and M girls attended a party. You are given a matrix A of N rows and M columns where Aij is 1 if the i-th boy likes the j-th girl, otherwise it will be 0. Note that it is not necessary that if a boy x likes girl y, then girl y should like boy x.
You know that if there are two different boys x and y, who both like girl z, then there will be a collision.
Can you calculate the number of different collisions at this party? Note that order of boys in the collision doesn't matter.

Input
The first line contains a single integer T denoting the number of test cases. Then T test cases follow.
The first line of each test case contains two space separated integers N, M denoting the number of boys and girls, respectively.
Each of the following N lines contain M characters, each of them is either '0' or '1'.

Output
For each test case output a single line containing an integer corresponding to the number of collisions at the party.

Constraints

1 ≤ T ≤ 100
1 ≤ N, M ≤ 10


Example
Input:
2
4 3
111
100
110
000
2 2
10
01

Output:
4
0


Explanation
Example Case 1. All three boys like the first girl, so there are (1, 2, 1), (1, 3, 1), (2, 3, 1) collisions with her. Boys 1 and 3 both like the second girl so this is one more collision. Only one boy likes the third girl, so there are no collisions with her and thus we have 4 collisions total.
Example Case 2. For each girl there is only one boy who likes her, so there are no collisions at all.
t = int(raw_input())

for i in range(t):
    n, m = map(int, raw_input().split())
    arr = []
    for i in range(n):
        arr.append(raw_input())
    
    coll = 0
    for i in range(m):
        x = 0
        for j in xrange(n):
            if arr[j][i] == '1':
                x += 1
        coll += x*(x-1)/2
    print coll