17. Extract the Nibble from an 8-bit Register

#include <stdio.h>

int lower_nibble(unsigned char reg){
    reg = reg & 0x0F;
    return reg;
}

int upper_nibble(unsigned char reg){
    reg = (reg & 0xF0) >> 4;
    return reg;
}

unsigned char extractNibble(unsigned char reg, int pos) {
    // Write your code here
    if (pos == 0){
        reg = lower_nibble(reg);
        return reg;
    }
    else {
        reg = upper_nibble(reg);
        return reg;
    }
}

int main() {
    unsigned char reg;
    int pos;
    scanf("%hhu %d", &reg, &pos);
    printf("%d", extractNibble(reg, pos));
    return 0;
}