#include<bits/stdc++.h> using namespace std; int main(){ int a; cin>>a; int g,s,b,q; g = a%10; s = a/10%10; b = a/100%10; q = a/1000; if(g != 0){ cout<<q<<g<<s<<b<<endl; }else{ cout<<g<<s<<b<<endl; } return 0; }