# Task
 CodeBots decided to make a gift for CodeMaster's birthday. They got a pack of candies of various sizes from the store, but instead of giving the whole pack they are trying to make the biggest possible candy from them. On each turn it is possible:
 
 ```
 to pick any two candies of the same size and merge
 them into a candy which will be two times bigger;

 to pick a single candy of an even size and split it 
 into two equal candies half of this size each.```
What is the size of the biggest candy they can make as a gift?

# Example

 For `arr = [2, 4, 8, 1, 1, 15]`, the output should be 16.
```
[2, 4, 8, 1, 1, 15] --> [2, 4, 8, 2, 15]
-->[4, 4, 8, 15] --> [8, 8, 15] --> [16, 15] -->choose 16
``` 

# Input/Output


 - [input] integer array `arr`

    Array of positive integers.

    Constraints:
    
    `5 ≤ inputArray.length ≤ 50,`
    
    `1 ≤ inputArray[i] ≤ 100.`


 - `[output]` an integer

```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

def _disabled_input(*args, **kwargs):
    raise RuntimeError("input() is disabled in callable mode")
builtins.input = _disabled_input

ns = {"__name__": "__judge__"}  # prevent if __name__ == "__main__" blocks
for _k, _v in list(globals().items()):
    if not _k.startswith("_"):
        ns[_k] = _v
_CODE = 'from collections import Counter\n\ndef obtain_max_number(arr):\n    c=dict(Counter(arr))\n    s=set(c)\n    r=0\n    while s:\n        m=min(s)\n        v=c[m]\n        s-={m}\n        M=m*2\n        if v//2:\n            c[M]=c.get(M,0)+v//2\n            s|={M}\n        r=max(r,m)\n    return r'
_co = compile(_CODE, USER_FILENAME, "exec")
exec(_co, ns, ns)

_target = None
_fn_name = 'obtain_max_number'
if _fn_name:
    if "Solution" in ns:
        try:
            _obj = ns["Solution"]()
            if hasattr(_obj, _fn_name):
                _target = getattr(_obj, _fn_name)
        except Exception:
            _target = None
    if _target is None and _fn_name in ns and callable(ns[_fn_name]):
        _target = ns[_fn_name]
# Fallback: if there's exactly one user-defined function, use it
if _target is None:
    _cands = [v for k, v in ns.items() if callable(v) and getattr(v, "__module__", "") in ("__judge__", "__main__")]
    _user_funcs = [c for c in _cands if getattr(c, "__name__", "").startswith("_") is False]
    if len(_user_funcs) == 1:
        _target = _user_funcs[0]
if _target is None:
    raise RuntimeError(f"Could not resolve callable '{_fn_name}'")

_raw = sys.stdin.read().strip()
if _raw:
    _parsed = json.loads(_raw)
    if isinstance(_parsed, dict):
        _kwargs = _parsed.get("kwargs", {})
        _args = _parsed.get("args", [])
    else:
        _args, _kwargs = _parsed, {}
else:
    _args, _kwargs = [], {}
if not isinstance(_args, (list, tuple)):
    _args = [_args]
_res = _target(*_args, **_kwargs)
try:
    sys.stdout.write(repr(_res) + "\n")
except Exception:
    pass

```

Measured memory_bytes: 9742