49번

package algorithmStudy;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

public class Test49_cwk {

	public static void main(String[] args) {
		String[] input = {"eat", "tea", "tan", "ate", "nat", "bat"};
		Solution49 sol = new Solution49();
		List<List<String>> anagrams = sol.groupAnagrams(input);
		System.out.println("[");
		for(int i = 0; i < anagrams.size(); i++)
		{
			if(i == anagrams.size() - 1)
			{
				System.out.println("  " + anagrams.get(i));
			} 
			else {
				System.out.println("  " + anagrams.get(i) + ",");
			}
		}
		System.out.println("]");
	}

}

class Solution49 {
	public List<List<String>> groupAnagrams(String[] input) {
		Map<String, List<String>> map = new HashMap<String, List<String>>();
		
		for(int i = 0; i < input.length; i++)
		{
			String str = input[i];
			
			char[] strCharArr = str.toCharArray();
			Arrays.sort(strCharArr);
			String key = String.valueOf(strCharArr);
			
			if(!map.containsKey(key))
			{
				map.put(key, new ArrayList<String>());
			}
			map.get(key).add(str);
		}
		
		return new ArrayList<List<String>>(map.values());
	}
}