#include <cstdio>
#include <list>

using namespace std;

int main() {

	char a, b;
	
	list<bool> input;
	list<bool> output;

	while(1) {

		// Read the input
		while(scanf("%c", &a) == 1 && a != '\n') {
			input . push_back(a - '0');
		}
		if(input.empty()) {
			return 0;
		}

		// Vysetrovani dvojic
		while( true ) {
			// Nacteni dvojice ab (v opacnem poradi - zasobnik)
			if( ! input.empty()) {
				b = input.back();
				input.pop_back();
			} else {
				b = 0;
			}

			output.push_back( !b );

			if( b == 0 ) { break; }

			if( ! input.empty() ) {
				a = input.back();
				input.pop_back();
			} else {
				a = 0;
			}
			
			output.push_back( !a );

			if( a == 1 ) { break; }
		}

		// Vypis
		bool first = true;

		while(! input.empty()) {
			if(input.front() == 1) first = false;
			if(!first)
				printf("%c", '0' + input.front());
			input.pop_front();
		}
		first = true;
		while(! output.empty()) {
			if(output.back() == 1) first = false;
			if(!first)
				printf("%c", '0' + output.back());
			output.pop_back();
		}
		if(first == true) printf("0");

		printf("\n");

	}
	return 0;
}