백준,1717,집합의 표현,유니온 파인드

Problem1717.java

import java.util.Scanner;

/**
 * 백준, 집합의 표현, 1717
 * 
 * @author User
 *
 */
public class Main {

	static int N;
	static int M;

	static int[] parent;

	public static void main(String[] args) {

		Scanner sc = new Scanner(System.in);
		N = sc.nextInt();
		M = sc.nextInt();

		parent = new int[N + 1];
		for (int i = 1; i <= N; i++)
			parent[i] = i;

		while (M-- > 0) {
			int type = sc.nextInt();
			int x = sc.nextInt();
			int y = sc.nextInt();

			if (type == 0) {
				union(x, y);
			} else if (type == 1) {
				System.out.println(find(x) == find(y) ? "YES" : "NO");
			}
		}

		sc.close();
	}

	public static int find(int x) {

		if (x == parent[x])
			return x;

		int root = find(parent[x]);
		parent[x] = root;
		return root;
	}

	public static void union(int x, int y) {
		x = find(x);
		y = find(y);
		parent[y] = x;
	}
}