#include<string>
#include<iostream>
#include<cmath>
#define MAXLEN 50
using namespace std;

struct StackType{
	char data[MAXLEN];
	int top;
};

StackType*STInit()
{
	StackType*s;
	if(s=new StackType){
		s->top=0;
		return s;
	}
	return NULL;
	
}

StackType*STPush(StackType*s,char e){
	if(s->top==MAXLEN)
		cout<<"栈溢出！"<<endl;
	s->data[++s->top]=e;
	return s;
}

char STPop(StackType*s){
	if(s->top==0){
		cout<<"栈为空！"<<endl;
		exit(0);
	}
	return s->data[s->top--];
}

int main()
{
	StackType*s;
	int i,len,sum=0;
	char e,h;
	cout<<"请输入二进制数："<<endl;
	s=STInit();
	cin>>e;
	
	while(e!='#'){
		
		
		STPush(s,e);
		cin>>e;
	}
	
	len=s->top;
	for(i=0;i<len;i++){
	
	sum=sum+(STPop(s)-48)*pow(2,double(i));
	
	}
	cout<<sum<<endl;
	system("pause");
		return sum;
	}