#include <bits/stdc++.h>
using namespace std;
string s,r;
int x,i;
int main(){
	cin>>s;
	string t[16]={"0000","0001","0010","0011","0100","0101","0110","0111","1000","1001","1010","1011","1100","1101","1110","1111"};
	for(i=0;i<s.size();i++){
		if(isdigit(s[i])){
			x=s[i]-'0';
		}else{
			x=s[i]-'A'+10;
		}
		r=r+t[x];
	}
	while(r[0]=='0'){
		r.erase(0,1);
	}
	if(r==""){
		cout<<0;
	}else{
		cout<<r;
	}
	return 0;
}