#include<bits/stdc++.h>
using namespace std;
int main()
{
	int n;
	cin>>n;
	int q = n / 1000;
	int b = n / 100 % 10;
	int s = n / 10 % 10;
	int g = n % 10;
	cout<<b*1000+q*100+g*10+s;
}

/**************************************************************
	Problem: 1619
	User: zhuangsongyu
	Language: C++
	Result: Accepted
	Time:8 ms
	Memory:2072 kb
****************************************************************/