leetcode 048 —— Anagrams

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

Note: All inputs will be in lower-case.
题意：找到重构的字符串

For example:

Input:　　["tea","and","ate","eat","den"]

Output:   ["tea","ate","eat"]

思路：要判断重构字符串，有两种方法，1：统计各个字符出现的次数 2：对字符串的字符进行排序

此处选择对字符串进行排序，如果，利用hash统计每种排序字符串出现的位置。

class Solution {
public:
vector<string> anagrams(vector<string>& strs) {
vector<string> res;
unordered_map<string, int> record;
string tmp;
for (int i = 0; i < strs.size(); i++){
tmp = strs[i];
sort(tmp.begin(), tmp.end());
if (record.find(tmp) == record.end()){//tmp尚未被统计仅map
record[tmp] = i;
}
else{
if (record[tmp] >= 0){ //如果tmp第er次被统计，则键值赋值为-1
res.push_back(strs[record[tmp]]);
record[tmp] = -1;
}
res.push_back(strs[i]);
}
tmp.clear();
}
return res;
}
};