Hashing - GitDeveloperKim/DreamEach GitHub Wiki

hm = new HashMap<>();						
							
// N input -> make hash table 
int indexforHash = 0;
st = new StringTokenizer(br.readLine(), " ");
for (int i = 1 ; i <= N; i++) {
	int num= Integer.parseInt(st.nextToken());
	if (hm.get(num) == null) {
		hm.put(num, new ArrayList<>());
	} 
	hm.get(num).add(indexforHash++); // {key: num, value: {indexforHash,,,}}
}