Extract the Nibble from an 8-bit Register

Code

#include <stdio.h>

typedef enum {
lower=0,
upper=1

}nibble;

unsigned char extractNibble(unsigned char reg, int pos) {
    
    if(pos==lower)
        reg=reg&0x0F;
    else 
        reg &=((reg&0xF0)>>4);

   


    return reg;
}

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

Solving Approach