Extract the Nibble from an 8-bit Register

Code

#include <stdio.h>

#define UPPER_NIBBLE    0xF0
#define LOWER_NIBBLE    0x0F
unsigned char extractNibble(unsigned char reg, int pos) {
    // Write your code here
    if(pos)
    {
        reg = (reg & UPPER_NIBBLE)>>4;
    }
    else
    {
        reg = (reg & LOWER_NIBBLE);
    }
    return reg;
}

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

Solving Approach