17. Extract the Nibble from an 8-bit Register

#include <stdio.h>

unsigned char extractNibble(unsigned char reg, int pos) {
    // Write your code here
    int x=0;
    for(int i=0;i<4;i++)
    {
        x = x | (1<<i);
    }
    if(pos==0)
    return (reg & x);
    else
    return ((reg>>4) & x);
}

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