#include <cstdio>
#include <cstring>
#include <algorithm>

using namespace std;

typedef long long ll;

char s[1000100];

int main()
{
    while (scanf("%s", s) == 1) {
        int len = strlen(s);
        reverse(s, s+len);
        s[len++] = '0';
        s[len++] = '0';
        int zb = 1;
        for (int i = 0; ; i++) {
            if (i % 2 == 0) {
                if (s[i] == '0') {
                    s[i] = '1';
                    break;
                } else {
                    s[i] = '0';
                }
            } else {
                if (s[i] == '0') {
                    s[i] = '1';
                } else {
                    s[i] = '0';
                    break;
                }
            }
        }
        while (s[len-1] == '0') {
            len--;
        }
        reverse(s, s+len);
        if (len == 0) {
            printf("0\n");
        } else {
            s[len] = 0;
            printf("%s\n", s);
        }
    }
    return 0;
}