[LeetCode&Python] Problem 383. Ransom Note

最新推荐文章于 2022-02-26 19:04:12 发布

转载最新推荐文章于 2022-02-26 19:04:12 发布 · 447 阅读

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原文链接：http://www.cnblogs.com/chiyeung/p/10048347.html

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#python

本文介绍了一种解决勒索信问题的字符串匹配算法。该算法通过使用collections模块中的Counter类，统计magazine字符串中各字符出现次数，然后遍历ransomNote字符串，判断其是否能由magazine中的字符构成，每使用一次字符则计数减一，最终返回是否成功构造的结果。

Given an arbitrary ransom note string and another string containing letters from all the magazines, write a function that will return true if the ransom note can be constructed from the magazines ; otherwise, it will return false.

Each letter in the magazine string can only be used once in your ransom note.

Note:
You may assume that both strings contain only lowercase letters.

canConstruct("a", "b") -> false
canConstruct("aa", "ab") -> false
canConstruct("aa", "aab") -> true

from collections import Counter
class Solution(object):
    def canConstruct(self, ransomNote, magazine):
        """
        :type ransomNote: str
        :type magazine: str
        :rtype: bool
        """
        c=Counter(magazine)
        for i in ransomNote:
            if c[i]==0 or i not in c:
                return False
            else:
                c[i]-=1
        return True

转载于:https://www.cnblogs.com/chiyeung/p/10048347.html