#include <stdio.h>

int main()
{
	char c;
	int number = 0;

	scanf("%c", &c);
	while ((c == '0') || (c == '1'))
	{
		number = number * 2 + (c - '0');
		scanf("%c", &c);
	}

	printf("Decimal value is %d\n", number);
}