Extract the Nibble from an 8-bit Register

Code

#include <stdio.h>

unsigned char extractNibble(unsigned char reg, int pos) {
    // Write your code here
    if(pos==1){
    reg=(reg>>4)&0x0F;
    }
    else{
        reg=(reg&0x0F);
    }
    return reg;
}

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

Solving Approach

You only want that nibble so you make others 0 by using 0x0F as per the requirement that value changes.