#include<bits/stdc++.h>
using namespace std;
int main(){
	int a,b,c,d,h,s;
	cin>>a;
	b=a%10;
	c=a/10%10;
	d=a/100%10;
	h=a/1000%10;
	s=h+d*10+c*100+b*1000;
	cout<<s;
}
/**************************************************************
	Problem: 1616
	User: toughuatao1
	Language: C++
	Result: Wrong Answer
****************************************************************/