LeetCode: Anagrams && HashMap

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

Note: All inputs will be in lower-case.

Solution:

Use a HashMap to store sorted strings. If two strings are anagrams, they are the same after being sorted.

	public ArrayList<String> anagrams(String[] strs) {
	ArrayList<String> ret = new ArrayList<String>();
	Map<String, ArrayList<String>> map = new HashMap<String, ArrayList<String>>();
	if(strs==null || strs.length == 0) return ret;
	for(int i=0; i< strs.length; i++){
	char[] temp = strs[i].toCharArray();
	Arrays.sort(temp);
	String sortedStr = new String(temp);
	if(map.containsKey(sortedStr)){
	map.get(sortedStr).add(strs[i]);
	}
	else{
	ArrayList<String> newArr = new ArrayList<String>();
	newArr.add(strs[i]);
	map.put(sortedStr, newArr);
	}
	}
	for(ArrayList<String> arrs : map.values()){
	if(arrs.size()>1)
	ret.addAll(arrs);
	}
	return ret;
	}

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