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.

```python

USER_FILENAME = "<user_code>"
import sys, json, builtins
import math, heapq, bisect, itertools, functools, collections, statistics, fractions, decimal, operator, array, random, re, string, os, pathlib
try:
    import resource as _res
except Exception:
    _res = None
from collections import Counter, defaultdict, deque, OrderedDict
from functools import lru_cache, reduce
from itertools import accumulate, permutations, combinations, product
from math import gcd, ceil, floor, sqrt
from decimal import Decimal
try:
    from typing import *
except Exception:
    pass
try:
    sys.setrecursionlimit(1_000_000)
except Exception:
    pass
try:
    import site as _site
    try:
        _sys_sites = _site.getsitepackages() if hasattr(_site, "getsitepackages") else []
        for _p in _sys_sites:
            if _p and _p not in sys.path:
                sys.path.append(_p)
    except Exception:
        pass
    try:
        _usp = _site.getusersitepackages()
        if isinstance(_usp, str):
            _usp = [_usp]
        for _p in _usp:
            if _p and _p not in sys.path:
                sys.path.append(_p)
    except Exception:
        pass
except Exception:
    pass

ns = {"__name__": "__main__"}
for _k, _v in list(globals().items()):
    if not _k.startswith("_"):
        ns[_k] = _v
_CODE = "def fact(i):\n a = i\n while a > 1:\n  i += (a-1)\n  a = a - 1\n return i\n\nfor _ in range(int(input())):\n n, m = list(map(int, input().split()))\n matrix = [0] * m\n for _ in range(n):\n  s = input()\n  for i in range(len(s)):\n   if s[i] == '1':\n    matrix[i] += 1\n coll = [fact(matrix[i]-1) for i in range(m) if matrix[i] > 1]\n print((sum(coll) if coll else 0))# cook your dish here\n"
_co = compile(_CODE, USER_FILENAME, "exec")
exec(_co, ns, ns)

```

Measured memory_bytes: 13311