#include<bits/stdc++.h>
using namespace std;
char zh(string k)
{
    int t = 1,r = 0;
    char c;
    for(int i = k.size()-1;i>=0;i--)
    {
        r = r + (k[i]-48) * t;
        t = t * 2;
    }
    if(r>9)
    {
        c=r+55;
    }
    else
    {
        c=r+48;
    }
    return c;
}
int main()
{
    string n,m;
    cin>>n;
    if(n.size() % 4 == 1)
    {
        n = "000" + n;
    }
    if(n.size() % 4 == 2)
    {
        n = "00" + n;
    }
    if(n.size() % 4 == 3)
    {
        n = "0" + n;
    }
    for(int i = 0;i<n.size();i = i + 4)
    {
        m = n.substr(i,4);
        cout<<zh(m);
    }
}
/**************************************************************
	Problem: 1294
	User: wuyichen
	Language: C++
	Result: Accepted
	Time:8 ms
	Memory:2076 kb
****************************************************************/