[백준] 5014 : 스타트링크 - JAVA(자바) - 사좋배 공유

 

 

import java.util.LinkedList;
import java.util.Queue;
import java.util.Scanner;

public class Main {
	static int Fsize;
	static int Start;
	static int Ges;
	static int Up;
	static int Down;
	static int result;
	static int arr[];
	static Queue q;
	static int dx[];
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		Fsize = sc.nextInt();
		Start = sc.nextInt();
		Ges = sc.nextInt();
		Up = sc.nextInt();
		Down = sc.nextInt();
		arr= new int [Fsize+1];
		q = new LinkedList();
		q.add(new pos(Start,0));

		if(Start==Ges) {
			System.out.println("0");
			return;
		}
		BFS();
		if(result==0) {
			System.out.println("use the stairs");
			return;
		}
		System.out.println(result);

	}
	private static void BFS() {
		while(!q.isEmpty()) {
			pos temp= q.poll();
			int number = temp.number;
			int count = temp.count;
			if(number == Ges) {
				result= count;
				q.clear();
				return;
			}
			for(int i=0;i<2;i++) {
				int rx=0;
				if(i==0) {
					rx = number+Up;
				}
				else if(i==1) {
					rx = number-Down;
				}
				if(rx<0||rx>Fsize||arr[rx]==1) {
					continue;
				}
				arr[rx]=1;
				q.add(new pos(rx,count+1));
			}
		}
	}
	public static class pos {
		int number;
		int count;
		pos(int number,int count){
			this.number=number;
			this.count=count;
		}

	}

}