Group Anagrams

Given an array of strings strs, group the anagrams together. You can return the answer in any order.

An Anagram is a word or phrase formed by rearranging the letters of a different word or phrase, typically using all the original letters exactly once.

Example 1:

Input: strs = ["eat","tea","tan","ate","nat","bat"]
Output: [["bat"],["nat","tan"],["ate","eat","tea"]]

Example 2:

Input: strs = [""]
Output: [[""]]

Example 3:

Input: strs = ["a"]
Output: [["a"]]

Constraints:

  • 1 <= strs.length <= 104
  • 0 <= strs[i].length <= 100
  • strs[i] consists of lowercase English letters.

Solution

Java
class Solution {
    public List<List<String>> groupAnagrams(String[] strs) {
        Map<String, List<String>> map = new HashMap<String, List<String>>();
        for(String s : strs) {
            char chArr[] = s.toCharArray();
            Arrays.sort(chArr);
            String Sch = new String(chArr);
            if(map.containsKey(Sch)){
                map.get(Sch).add(s); 
            } 
            else {
                List<String> strings = new ArrayList<String>();
                strings.add(s);
                map.put(Sch, strings);
            }
        }
        List<List<String>> result = new ArrayList<List<String>>();
        for(List<String> val : map.values()) {
            result.add(val);
        }

        return result;
    }
}
Agnibha Chandra