#include <stdio.h>

void hex(unsigned n){
	if(n==0)
		return;
	hex(n/16);
	if(n%16>9)
		putchar('A'+n%16-10);
	else
		putchar('0'+n%16);
}

int main(){
	unsigned n;
	scanf("%u", &n);
	hex(n);
	putchar('\n');
	return 0;
}