17. Extract the Nibble from an 8-bit Register

#include <stdio.h>

unsigned char extractNibble(unsigned char reg, int pos) {
    unsigned char RetVal = reg;
    if (pos) { return ((RetVal & 0xF0) >> 4); }
    return ((RetVal & 0x0F));
}

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