Day_87_GroupAnagrams.java

import java.util.*;

class Solution {
    public List<List<String>> groupAnagrams(String[] strs) {
        Map<String, List<String>> map = new HashMap<>();
        for (String s : strs) {
            char[] c = s.toCharArray();
            Arrays.sort(c);
            String sorted = new String(c);
            if (!map.containsKey(sorted)) {
                map.put(sorted, new ArrayList<String>());
            }
            map.get(sorted).add(s);
        }
        return new ArrayList<List<String>>(map.values());
    }
}