#include<bits/stdc++.h> using namespace std; int main(){ int n,a[5]; cin>>n; a[2]=n/1000; n%=1000; a[3]=n/100; n%=100; a[4]=n/10; n%=10; a[5]=n; cout<<a[5]<<a[4]<<a[3]<<a[2]; return 0; }