#include <iostream>
#include <vector>
using namespace std;

int main() {
    string str;
    while (cin >> str) { 
        str=str.substr(2);
        long long answer=0;
        for(int i=0;i<str.size();i++)
        {
            answer*=16;
            char x=str[i];
            if(x>='0'&&x<='9')
            answer+=str[i]-'0';
            else{
                answer+=str[i]-'A'+10;
            }

        }
        cout<<answer<<endl;
    }
}