Extract the Nibble from an 8-bit Register

Code

#include <stdio.h>

unsigned char extractNibble(unsigned char reg, int pos) {
  
  if(pos==0)
  {
    reg = reg & 0X0F;
  }
else if(pos==1)
{
    reg = (reg>>4) & 0X0F;
}
else
{
    printf("invalid operation...\n");
}
   return reg;
   
}

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

Solving Approach