17. Extract the Nibble from an 8-bit Register

#include<stdio.h>
unsigned char nibble(unsigned char reg, int pos){
    if(pos==0){
        return reg & 0x0F;
    }
    else{
        return(reg>>4)&0x0F;
    }
}
int main(){
    unsigned char reg;
    int pos;
    scanf("%hhu %d",&reg,&pos);
    printf("%d",nibble(reg,pos));
    return 0;
}