每个string sort。。。然后这个作为group的key
class Solution { public: vector<string> anagrams(vector<string> &strs) { unordered_map<string , vector<string> >group; for(int i = 0 ; i < strs.size() ; i++) { string k = strs[i]; sort(k.begin() , k.end()); group[k].push_back(strs[i]); } vector<string> ans; for(auto it = group.begin() ; it != group.end() ; it++) { if(it -> second.size() > 1) ans.insert(ans.end() , it->second.begin() , it -> second.end()); } return ans; } };
by 1957