题目
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.
解题思路
将勒索信和杂志的字符串都转成计数器，遍历勒索信中的每个字母，如果出现的次数都小于杂志中出现的次数则是True否则为False
代码
from collections import Counter
class Solution:
def canConstruct(self, ransomNote: str, magazine: str) -> bool:
ct_ransom = Counter(ransomNote)
ct_magazine = Counter(magazine)
for key in ct_ransom:
if ct_ransom[key] > ct_magazine[key]:
return False
return True
