[백준:1697] 숨바꼭질 - JAVA

import java.util.*;
public class Main {

	static int[] visit= new int[100001];
	static int start;
	static int end;
	
	public static void bfs(int v) {
		Queue<Integer> q = new LinkedList<>();
		
		q.add(v);
		visit[v] = 1;
		
		while (!q.isEmpty()) {
            int temp = q.poll();

            for (int i = 0; i < 3; i++) {
                int next;

                if (i == 0) {
                    next = temp + 1;
                } else if (i == 1) {
                    next = temp - 1;
                } else {
                    next = temp * 2;
                }

                if (next == end) {
                    System.out.println(visit[temp]);
                    return;
                }

                if (next >= 0 && next < visit.length && visit[next] == 0) {
                    q.add(next);
                    visit[next] = visit[temp] + 1;
                }
            }
        }
	}
	public static void main(String[] args) {
		
		Scanner scan = new Scanner(System.in);
		
		start = scan.nextInt();//수빈
		end = scan.nextInt();//동생
		
		if(start == end)
			System.out.println(0);
		else 
			bfs(start);
		
		scan.close();
	}
}