#include <bits/stdc++.h>
using namespace std;
char fun(string a)
{
	int k=1,s=0;
	for (int i=a.size()-1;i>=0;i--)
	{
		s=s+(a[i]-48)*k;
		k=k*2;
	}
	if (s>=10) return char(s+55);
	else return char(s+48); 
}
int main()
{
	string s,r,l;
	cin>>s;
	int t=s.size();
	if (t%4!=0)
	{
		for (int i=1;i<=4-t%4;i++)
		{
			s="0"+s;
		//	cout<<s<<endl;
		}
	}
	for (int i=0;i<s.size();i+=4)
	{
		l=s.substr(i,4);
	//	cout<<l<<endl;
		r=r+fun(l);
	}
	cout<<r<<endl;
	return 0;
}
/**************************************************************
	Problem: 1294
	User: admin
	Language: C++
	Result: Accepted
	Time:9 ms
	Memory:2080 kb
****************************************************************/