#include<bits/stdc++.h>
using namespace std;
char zh(string k)
{
	int r=0;
	int t=1;
	char c;
	for(int i=k.size()-1;i>=0;i--)
	{
		r=r+(k[i]-48)*t;
		t=t*2;
	}
	if(r<10)
	{
		c=r+48;
	}
	else
	{
		c=r+55;
	}
	return c;
}
int main()  
{
	string n,t;
	cin>>n;
	if(n.size()%4==1)
	{
		n="000"+n;
	}
	else if(n.size()%4==2)
	{
		n="00"+n;
	}
	else if(n.size()%4==3)
	{
		n="0"+n;
	}
	for(int i=0;i<n.size();i=i+4)
	{
		t=n.substr(i,4);
		cout<<zh(t);
	}
	return 0;
}
/**************************************************************
	Problem: 1294
	User: chenkexin
	Language: C++
	Result: Accepted
	Time:8 ms
	Memory:2076 kb
****************************************************************/