#include<iostream>
#include<algorithm>
#include<vector>
#include<string>
#include<set>
#include<cmath>
using namespace std;

int main()
{
    string s;
    while(cin>>s)
    {
        int sum=0;
        int n=s.size();
        for(int i=0;i<n;i++)
        {
            if(s[i]=='0') continue;
            sum+=(s[i]-'0')*(pow(2,n-i)-1);
        }
        cout<<sum<<endl;
    }
}