17. Extract the Nibble from an 8-bit Register

#include <stdio.h>


// 0x1001 1000
// Lấy upper nibble: 1001 <= (0x1001 1000 >> 4)
// Lấy lower niblle: 1000 <= (0x1001 1000 & 0x1111)

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

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