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 mask;
    if(pos){
        mask = 0xF0u;
        return (reg & mask) >> 4u;
    }
    else{
        mask = 0x0Fu;
        return reg & mask;
    }
}

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