#include <cstdio>
#include <vector>

using namespace std;

int main()
{
while (true)
{
	vector<bool> in;
	in.push_back(false);
	char c;
	while (true)
	{
		if (scanf("%c", &c) == EOF)
			return 0;
//		if (c == EOF) return 0;
		if (c != '\n')
			in.push_back(c == '1');
		else
			break;
	}

	in[in.size() - 1] = !in[in.size() - 1];
	bool even = false;
	for (int i = in.size() - 2; i >= 0; --i)
	{
		if (even == in[i + 1])
		{
			in[i] = !in[i];
		}
		else
		{
			break;
		}

		even = !even;
		// treba dopisat pred
		if (i == 0)
		{
			in.insert(in.begin(), false);
			++i;
		}
	}

	int i = 0;
	const int size = in.size();
	while (!in[i] && i < size)
		++i;

//	const int size = in.size();
	if (i == size)
		putchar('0');
	else
		for (i; i < size; ++i)
		{
			putchar(in[i] ? '1' : '0');
		}

	putchar('\n');
}
	return 0;
}