#include <stdio.h>
#include <stdint.h>
void print_hex(uint16_t num) {
if (num==0) printf ("0");
char c[16];
int i = 0;
while (num>0) {
int remainder = num % 16;
if (remainder >= 10) c[i++] = (remainder - 10) + 'A';
else c[i++] = remainder + '0';
num/=16;
}
for (int j = i-1; j >=0; j--) {
printf("%c", c[j]);
}
}
int main() {
uint16_t num;
scanf("%hu", &num);
print_hex(num);
return 0;
}