Devu is a disastrous oracle: his predictions about various events of your life are horrifying. Instead of providing good luck, he "blesses" you with bad luck. The secret behind his wickedness is a hidden omen which is a string of length m. On your visit to him, you can ask a lot of questions about your future, each of which should be a string of length m. In total you asked him n such questions, denoted by strings s1, s2, ... , sn of length m each. Each of the question strings is composed of the characters 'a' and 'b' only.

Amount of bad luck this visit will bring you is equal to the length of longest common subsequence (LCS) of all the question strings and the hidden omen string. Of course, as the omen string is hidden, you are wondering what could be the least value of bad luck you can get.

Can you find out what could be the least bad luck you can get? Find it fast, before Devu tells you any bad omens.

-----Input-----
The first line of the input contains an integer T denoting the number of test cases. The description of T test cases follows.
First line of each test case contains a single integer n denoting number of strings.
For each of next n lines, the ith line contains the string si.

-----Output-----
For each test case, output a single integer corresponding to the answer of the problem. 


-----Constraints-----
- All the strings (including the hidden omen) contain the characters 'a' and 'b' only.

Subtask #1: (40 points) 

- 1 ≤ T, n, m ≤ 14

Subtask #2: (60 points) 

- 1 ≤ T, n, m ≤ 100

-----Example-----
Input:3
2
ab
ba
2
aa
bb
3
aabb
abab
baab

Output:1
0
2

-----Explanation-----
In the first example, the minimum value of LCS of all the strings is 1, the string by oracle can be one of these {aa, ab, ba, bb}. 

In the second example, whatever string oracle has does not matter, LCS will always be zero.

```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 = 't=eval(input())\nfor qq in range(t):\n n=eval(input())\n s=input()\n amin=0\n bmin=0\n for x in s:\n  if x =="a":amin+=1\n  else:bmin+=1\n #print s,amin,bmin\n for cc in range(n-1):\n  s=input()\n  ca=0\n  cb=0\n  for x in s:\n   if x=="a":ca+=1\n   else:cb+=1\n  amin=min(ca,amin)\n  bmin=min(cb,bmin)\n #   print s,amin,bmin\n print(min(amin,bmin))'
_co = compile(_CODE, USER_FILENAME, "exec")
exec(_co, ns, ns)

```

Measured memory_bytes: 17607