LeetCode-242-有效的字母异位词

Leetcode 242.Valid Anagram

Given two strings s and t , write a function to determine if t is an anagram of s.

Example：
Input: s = “anagram”, t = “nagaram”
Output: true

Input: s = “rat”, t = “car”
Output: false

# @Author：Kilien
# @lc app=leetcode id=242 lang=python3
#
# [242] Valid Anagram
#
class Solution:

# 思路：数组排序后比较差异
#    def isAnagram(self, s: str, t: str) -> bool:
#        return sorted(s) == sorted(t)

# 思路：手动模拟hashtable，将字符串”a-z“的ASCII码作key，
#计数求差异
    def isAnagram(self, s: str, t: str) -> bool:
        arr1, arr2 = [0]*26, [0]*26
        for i in s:
            arr1[ord(i) - ord('a')] += 1
        for i in t:
            arr2[ord(i) - ord('a')] += 1
        return arr1 == arr2

# 思路：map计数，对比计数差异
"""
    def isAnagram(self, s: str, t: str) -> bool:
        dict1, dict2 = {}, {}
        for item in s:
            dict1[item] = dict1.get(item,0) + 1
        for item in t:
            dict2[item] = dict2.get(item,0) + 1
        return dict1 == dict2
"""