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

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