#include<bits/stdc++.h>
using namespace std;
int n,m,z,x,c;
int main(){
cin>>n;
for(int i=0;i<4;i++){
cout<<n%10;
n/=10;
}
}
/**************************************************************
Problem: 1029
User: zhengzihao
Language: C++
Result: Wrong Answer
****************************************************************/