17. Extract the Nibble from an 8-bit Register

#include <stdio.h>

unsigned char extractNibble(unsigned char reg, int pos) {
    // Write your code here
    unsigned char lower_nibble, upper_nibble;
    if(!pos){
        lower_nibble= reg & 0x0F;
        return lower_nibble;
    }
    else{
        upper_nibble = (reg>>4) & 0x0F;
        return upper_nibble;
    }
}

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