#include <iostream>
using namespace std;
int main() {
int a;
cin >> a;
int i = 0;
char b[100];
if (a == 0) {
cout << "0";
} else {
while (a != 0) {
if (a % 16 >= 10)
b[i++] = a % 16 + 'A' -10;
else
b[i++] = a % 16 + '0';
a = a / 16;
}
}
for (int k = i - 1; k >= 0; k--)
cout << b[k];
return 0;
}