After learning a lot about space exploration, a little girl named Ana wants to change the subject.

Ana is a girl who loves palindromes (string that can be read the same backwards as forward). She has learned how to check for a given string whether it's a palindrome or not, but soon she grew tired of this problem, so she came up with a more interesting one and she needs your help to solve it:

You are given an array of strings which consist of only small letters of the alphabet. Your task is to find how many palindrome pairs are there in the array. A palindrome pair is a pair of strings such that the following condition holds: at least one permutation of the concatenation of the two strings is a palindrome. In other words, if you have two strings, let's say "aab" and "abcac", and you concatenate them into "aababcac", we have to check if there exists a permutation of this new string such that it is a palindrome (in this case there exists the permutation "aabccbaa"). 

Two pairs are considered different if the strings are located on different indices. The pair of strings with indices $(i,j)$ is considered the same as the pair $(j,i)$.


-----Input-----

The first line contains a positive integer $N$ ($1 \le N \le 100\,000$), representing the length of the input array.

Eacg of the next $N$ lines contains a string (consisting of lowercase English letters from 'a' to 'z') — an element of the input array. 

The total number of characters in the input array will be less than $1\,000\,000$.


-----Output-----

Output one number, representing how many palindrome pairs there are in the array.


-----Examples-----
Input
3
aa
bb
cd

Output
1

Input
6
aab
abcac
dffe
ed
aa
aade

Output
6



-----Note-----

The first example:  aa $+$ bb $\to$ abba. 

The second example:  aab $+$ abcac $=$ aababcac $\to$ aabccbaa aab $+$ aa $=$ aabaa abcac $+$ aa $=$ abcacaa $\to$ aacbcaa dffe $+$ ed $=$ dffeed $\to$ fdeedf dffe $+$ aade $=$ dffeaade $\to$ adfaafde ed $+$ aade $=$ edaade $\to$ aeddea

```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 = "n=int(input())\ns=[0]*n\nfor i in range (n):\n    s[i]=input()\ndic={}\nans=0\nfor i in range (n):\n    temp=0\n    for k in range(len(s[i])):\n        temp^=(1<<(ord(s[i][k])-ord('a')))\n    #print(temp,s[i])\n    if temp in list(dic.keys()):\n        ans=ans+dic[temp]\n    for j in range (26):\n        chk=temp\n        chk^=(1<<j)\n        if chk in list(dic.keys()):\n            ans=ans+dic[chk]\n    if temp in list(dic.keys()):\n        dic[temp]+=1\n    else:\n        dic[temp]=1\n   # print(dic[temp])\nprint(ans)\n"
_co = compile(_CODE, USER_FILENAME, "exec")
exec(_co, ns, ns)

```

Measured memory_bytes: 13367