27. Extract Bit Field from 16-bit Register

#include <stdio.h>
#include <stdint.h>
uint8_t extract_field(uint16_t reg) {
    uint16_t mask = 0x1F << 4; 
    uint16_t masked_value = reg & mask;
    uint8_t field_value = masked_value >> 4;
    return field_value;
}
int main() {
    uint16_t reg;
    scanf("%hx", &reg);
    printf("%u", extract_field(reg));
    return 0;
}