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 a = 0;
    if(pos == 0) {
        a |= (reg & 0x0F);
    } else {
        a |= ((reg >> 4) & 0x0F);
    }

    return a;
}

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