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

1. 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:
               continue
           allset.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 result
   
   astr = ["eat", "tea", "tan", "ate", "nat", "bat"]
   print(groupAnagrams_ext1(astr))
   # 运行结果
   # [['eat', 'tea', 'ate'], ['tan', 'nat'], ['bat']]
   

2. 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 result
   
   astr = ["eat", "tea", "tan", "ate", "nat", "bat"]
   print(groupAnagrams_ext2(astr))
   # 运行结果
   # [['eat', 'tea', 'ate'], ['tan', 'nat'], ['bat']]
   

3. 使用字典和元组

   def groupAnagrams_ext3(self, strs):
       from collections import Counter
       anagrams = {}
       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']]
   

   一日练，一日功，一日不练十日空

   may the odds be ever in your favor ~