#include <bits/stdc++.h>
using namespace std;
using ll = long long;
#define fi first
#define se second
int main(){
    string s;
    cin >> s;
    if(s.back() == '1') s.back() = '0';
    if(s.back() == '0') s.back() = '1';
    cout << s << endl;
    return 0;
}