#include <bits/stdc++.h>
using namespace std;

int main(){
    ios::sync_with_stdio(false);
    cin.tie(0);
    string s; cin >> s;
    int ss = s.size();
    s[ss-1] = s[ss-1]  == '1'? '0': '1';
    cout << s << '\n';
    return 0;
}