Extract the Nibble from an 8-bit Register

Code

#include <stdio.h>

unsigned char extractNibble(unsigned char reg, int pos) {
   if(pos==0){
     return(reg & 0b00001111);
}
else{return((reg & 0b11110000)>>4);}

}

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

Solving Approach

Mask off the unnecessary bits, and shift the bits to the right in the case of the upper section, couldn't use hex values on phone for some reason