Description
Given an array of strings, group anagrams together.
Example
Input: ["eat", "tea", "tan", "ate", "nat", "bat"],
Output:
[
["ate","eat","tea"],
["nat","tan"],
["bat"]
]
Note
All inputs will be in lowercase.
The order of your output does not matter.
Solution 1(C++)
class Solution {
public:
vector<vector<string>> groupAnagrams(vector<string>& strs) {
unordered_map<string, multiset<string>> mp;
for (string s : strs) {
string t = s;
sort(t.begin(), t.end());
mp[t].insert(s);
}
vector<vector<string>> anagrams;
for (auto m : mp) {
vector<string> anagram(m.second.begin(), m.second.end());
anagrams.push_back(anagram);
}
return anagrams;
}
};
Solution 2(C++)
class Solution {
public:
vector<vector<string>> groupAnagrams(vector<string>& strs) {
unordered_map <string, vector<string>> hashmap;
for(int i = 0 ; i<strs.size(); i++){
string key = strs[i];
sort(strs[i].begin(), strs[i].end());
hashmap[strs[i]].push_back(key);
}
vector<vector<string>> solution;
unordered_map<string, vector<string>> :: iterator i ;
for(i = hashmap.begin() ; i!=hashmap.end(); i++){
solution.push_back(i->second) ;
}
return solution;
}
};
算法分析
算法没啥好多多说的,主要是STL主要数据结构要熟练使用。
程序分析
请复习: