#include <stdio.h>
#include <stdint.h>
uint8_t extract_field(uint16_t reg) {
// Your logic here
uint8_t result=0;
uint16_t mask=0x1F<<4;
result |=(reg&mask)>>4;
return result;
}
int main() {
uint16_t reg;
scanf("%hx", ®);
printf("%u", extract_field(reg));
return 0;
}