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