#include<bits/stdc++.h>
using namespace std;
int main(){
	string s,s1,s2,n="0123456789ABCDDEF";
	int o=0;
	cin>>s;
	if(s.size()%4==1)  s="000"+s;
	else if(s.size()%4==2)  s="00"+s;
	else if(s.size()%4==3)  s="0"+s;
	for(int i=0;i<s.size();i=i+4){
		s1=s.substr(i,4);
		  cout<<n+[(s1[0]-'0')*8+(s1[1]-'0')*4+(s1[2]-'0')*2+(s1[3]-'0')*1];
		
	}
	
	return 0;
}

/**************************************************************
	Problem: 1294
	User: huxuanchen
	Language: C++
	Result: Compile Error
****************************************************************/