#9.20
#include <bits/stdc++.h>
using namespace std;
int a[110] = {'0'};
int idx = -1;
//出栈
char pop()
{
idx--;
return a[idx+1];
}
//压栈
void push(int x)
{
idx++;
a[idx] = x;
}
int main(void)
{
int n;
cin >> n;
while (n!=0)
{
int mod = n%16;
if(mod>=10)
mod = 'A'+mod-10;
else
mod = '0'+mod;
push(mod);
N=N/16;
}
while(idx>=0)
{
cout<<pop();
}
}
a = int (input())
ls = list()
while a!=0:
ls.append(a%2)
a//=2
for i in range(len(ls)):
print(ls.pop(),end='')
print("\n")