Given a string s and an integer k.
Return the maximum number of vowel letters in any substring of s with length k.
Vowel letters in English are (a, e, i, o, u).
 
Example 1:
Input: s = "abciiidef", k = 3
Output: 3
Explanation: The substring "iii" contains 3 vowel letters.

Example 2:
Input: s = "aeiou", k = 2
Output: 2
Explanation: Any substring of length 2 contains 2 vowels.

Example 3:
Input: s = "leetcode", k = 3
Output: 2
Explanation: "lee", "eet" and "ode" contain 2 vowels.

Example 4:
Input: s = "rhythms", k = 4
Output: 0
Explanation: We can see that s doesn't have any vowel letters.

Example 5:
Input: s = "tryhard", k = 4
Output: 1

 
Constraints:

1 <= s.length <= 10^5
s consists of lowercase English letters.
1 <= k <= s.length

```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 = '# class Solution:\n#     def maxVowels(self, s: str, k: int) -> int:\n#         vowels = {\\"a\\", \\"e\\", \\"i\\", \\"o\\", \\"u\\"}\n#         m = 0\n#         for el in s[:k]:\n#             if el in vowels:\n#                 m += 1\n#         a = m\n#         for i in range(k, len(s)):\n#             if s[i] in vowels:\n#                 a += 1\n#             if s[i-k] in vowels:\n#                 a -= 1\n#             m = max(a,m)\n#         return m\n    \nclass Solution:\n    \n    # k = substring length. If sliding windows then left & right of sliding window should be different by k\n    def maxVowels(self, s: str, k: int) -> int:\n        is_a_vowel = lambda letter: letter in \'aeiou\'\n\n        count = 0\n        maximum_vowels = 0\n        \n        \n        left = 0\n        \n        for right in range(len(s)):\n            # moving right but not touching left pointer\n            if right < k:\n                count = count + 1 if is_a_vowel(s[right]) else count # add next vowel if present\n                maximum_vowels = max(maximum_vowels, count)\n            else:\n            # moving right and touching left pointer so that distance between pointers is always k\n                count = max(0, count-1) if is_a_vowel(s[left]) else count # letter is cut from substrg of k, so decrease count but not lower than 0\n                count = count + 1 if is_a_vowel(s[right]) else count # add next vowel if present\n                left = left + 1\n                maximum_vowels = max(maximum_vowels, count)\n        \n        return maximum_vowels'
_co = compile(_CODE, USER_FILENAME, "exec")
exec(_co, ns, ns)

_target = None
_fn_name = 'maxVowels'
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: 5672