백준 1914번 (하노이 탑) 자바 Java11

문제 : 하노이 탑

시간 제한 : 6 sec

메모리 제한 : 128 MB

 

import java.io.*;
import java.math.BigInteger;
import java.util.*;
 
public class Main {
    public static void main(String[] args) throws IOException{
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));
        int n = Integer.parseInt(br.readLine());
        BigInteger re = BigInteger.ONE;
        for (int i = 0; i < n; i++) {
            re = re.multiply(BigInteger.TWO);
        }
        re = re.subtract(BigInteger.ONE);
        System.out.println(re);
        if(n<=20)
            move(n,1,3);
 
        br.close();
        bw.flush();
        bw.close();
    }
 
 
    public static void move(int n, int i, int j) {
        // TODO Auto-generated method stub
        if(n==1) {
            System.out.println(i+" "+j);
            return;
        }
        if(n>1) {
            move(n-1,i,6-i-j);
        }
        System.out.println(i+" "+j);
        if(n>1) {
            move(n-1,6-i-j,j);
        }
 
    }
}