Python C++速解Leetcode迴文1400 Construct K Palindrome Strings

Python C++速解Leetcode迴文1400  Construct K Palindrome Strings

關鍵：偶數長度的回文字串中所有字母都出現偶數，奇數長度的回文字串中除了一個例外其他所有字母都出現偶數。

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The key observation: palindrome strings of even lengths have all letters even occurrences, palindrome strings of odd lengths have all letters even occurrences but except one letter with odd occurrence.

[Py3解答請進]

[codes on Leetcode]https://leetcode.com/problems/construct-k-palindrome-strings/solutions/6262071/only-consider-the-parity-of-freq-bitset-beats-100/

[C++ python使用DFS與奇偶測試解Leetcode1457 Pseudo Palindromic Paths in a Binary Tree]https://www.youtube.com/watch?v=StHXyYgavUU

[C, C++ ,python速解迴文Leetcode 2108 Find First Palindromic String in the Array]https://www.youtube.com/watch?v=eXhdv8jDpao

class Solution:
    def canConstruct(self, s: str, k: int) -> bool:
        n=len(s)
        if n<k: return False
        freq=[False]*26
        for c in s:
            freq[ord(c)-97]^=1
        return freq.count(True)<=k