leetcode - Anagrams

Given an array of strings, return all groups of strings that are anagrams.

Note: All inputs will be in lower-case.

class Solution {
public:
    std::vector
  
    anagrams(std::vector
   
     &strs) { std::vector
    
      res; std::map
     
       ans; for (int i = 0; i < strs.size(); i++) { std::string s = strs[i]; std::sort(s.begin(),s.end()); if(ans.find(s) != ans.end()) { if(ans[s] >= 0) { res.push_back(strs[ans[s]]); ans[s] = -1; } res.push_back(strs[i]); } else { ans.insert(std::make_pair(s,i)); } } return res; } };