Python算法题集_字母异位词分组

本文为Python算法题集之一的代码示例

题目49：字母异位词分组

说明：给你一个字符串数组，请你将 字母异位词 组合在一起，可以按任意顺序返回结果列表

字母异位词 ：是由重新排列原单词所有字母得到的新单词

使用同步数组list和检索集合set

def groupAnagrams_ext1(self, strs):iLen = len(strs)setlist = []for iIdx in range(iLen):setlist.append(sorted(strs[iIdx]))allset = []for aSet in setlist:if aSet in allset:continueallset.append(aSet)result=[]for aSetItem in allset:tmpResultItem=[]for iIdx in range(iLen):if setlist[iIdx] == aSetItem:tmpResultItem.append(strs[iIdx])result.append(tmpResultItem)return resultastr = ["eat", "tea", "tan", "ate", "nat", "bat"]
print(groupAnagrams_ext1(astr))
# 运行结果
# [['eat', 'tea', 'ate'], ['tan', 'nat'], ['bat']]

使用同步数组list和结果数组list

def groupAnagrams_ext2(self, strs):iLen = len(strs)sortlist = []for iIdx in range(iLen):sortlist.append(sorted(strs[iIdx]))result, resultsort=[], []for iIdx in range(iLen):if sortlist[iIdx] in resultsort:result[resultsort.index(sortlist[iIdx])].append(strs[iIdx])else:resultsort.append(sortlist[iIdx])result.append([strs[iIdx]])return resultastr = ["eat", "tea", "tan", "ate", "nat", "bat"]
print(groupAnagrams_ext2(astr))
# 运行结果
# [['eat', 'tea', 'ate'], ['tan', 'nat'], ['bat']]

使用字典和元组

def groupAnagrams_ext3(self, strs):from collections import Counteranagrams = {}for s in strs:counter = Counter(s)key = tuple(sorted(counter.items()))if key not in anagrams:anagrams[key] = []anagrams[key].append(s)return list(anagrams.values())astr = ["eat", "tea", "tan", "ate", "nat", "bat"]
print(groupAnagrams_ext3(astr))
# 运行结果
# [['eat', 'tea', 'ate'], ['tan', 'nat'], ['bat']]