#include <iostream>
#include <cstdio>
#include <cmath>
#include <string>
 
using namespace std;
 
void HanoiTower(int num, int from, int by, int to)
{
	if (num == 1) printf("%d %d\n", from, to);
	else
	{
		HanoiTower(num - 1, from, to, by);
		printf("%d %d \n", from, to);
		HanoiTower(num - 1, by, from, to);
	}
}
 
int main(void)
{
	int N;
	cin >> N;
 
	string a = to_string(pow(2, N));
 
	int x = a.find('.');				//pow 함수 결과가 실수형이기에 소수점 찾기
	a = a.substr(0, x);				//소수점 앞자리만 나오게하기
	a[a.length() - 1] -= 1;				//string a에 대한 마지막 위치의 인덱스 값에 -1
 
	cout << a << endl;
 
	if(N <= 20)
		HanoiTower(N, 1, 2, 3);
 
	return 0;
}

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