You are given a string S consisting of lowercase English letters.
Determine whether we can turn S into a palindrome by repeating the operation of swapping two adjacent characters. If it is possible, find the minimum required number of operations.

-----Constraints-----
 - 1 \leq |S| \leq 2 × 10^5
 - S consists of lowercase English letters.

-----Input-----
Input is given from Standard Input in the following format:
S

-----Output-----
If we cannot turn S into a palindrome, print -1. Otherwise, print the minimum required number of operations.

-----Sample Input-----
eel

-----Sample Output-----
1

We can turn S into a palindrome by the following operation:
 - Swap the 2-nd and 3-rd characters. S is now ele.

```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 = 'from collections import Counter\nclass BIT:\n    def __init__(self, n):\n        self.size = n\n        self.tree = [0] * (n + 1)\n \n    def sum(self, i):\n        s = 0\n        while i > 0:\n            s += self.tree[i]\n            i -= i & -i\n        return s\n \n    def add(self, i, x):\n        while i <= self.size:\n            self.tree[i] += x\n            i += i & -i\n\nS = input()\nN = len(S)\n\ncnt = 0\nSC = Counter(S)\nfor v in SC.values():\n    if v % 2:\n        cnt += 1\nif cnt > 1:\n    print(-1)\n    return\n\ngeta = 10**9+7\nT = [None]*N\ntable = Counter()\nidx = dict()\nctr = 0\nfor i, s in enumerate(S):\n    table[s] += 1\n    if table[s] <= SC[s]//2: \n        T[i] = ctr\n        idx[ord(s)*geta + table[s]] = ctr\n        ctr += 1\n        continue\n    if table[s] > (1+SC[s])//2:\n        T[i] = N - 1 - idx[ord(s)*geta+(SC[s] + 1 - table[s])]\n        continue\n    if SC[s] % 2 and table[s] == (SC[s]+1)//2:\n        T[i] = (N-1)//2\n        continue\nTr = [None]*N\nfor i, v in enumerate(T):\n    Tr[v] = i\nB = BIT(N)\nans = 0\nfor tr in Tr[::-1]:\n    ans += B.sum(tr + 1)\n    B.add(tr + 1, 1)\nprint(ans)'
_co = compile(_CODE, USER_FILENAME, "exec")
exec(_co, ns, ns)

```

Measured memory_bytes: