27. Extract Bit Field from 16-bit Register

#include <stdio.h>
#include <stdint.h>

#define BIT_POS 4
#define BIT_MASK 0x1f

#define EXTRACT(reg)  (reg = ((reg >> 4) & BIT_MASK))


uint8_t extract_field(uint16_t reg) {
    // Your logic here
    EXTRACT(reg);
    return reg;
}

int main() {
    uint16_t reg;
    scanf("%hx", &reg);
    printf("%u", extract_field(reg));
    return 0;
}