Leetcode: Anagrams

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

Note: All inputs will be in lower-case.

分析：此题的题意不是很明确，意思重新表述应该是一组string里面，有几个是anagram，找出这几个string。因为anagram具有相同个数的字符只是顺序有所改变，我们可以将string中字符排序后，再用一个unordered_map将anagram的几个string放到一起。代码如下：

class Solution {
public:
    vector<string> anagrams(vector<string> &strs) {
        vector<string> result;
        unordered_map<string, vector<string> > group;
        for(auto i:strs){
            string tmp = i;
            sort(tmp.begin(), tmp.end());
            group[tmp].push_back(i);
        }
        for(auto i = group.begin(); i != group.end(); i++){
            if(i->second.size() > 1)
                result.insert(result.end(), i->second.begin(), i->second.end());
        }
        return result;
    }
};