#include <stdio.h>
unsigned char extractNibble(unsigned char reg, int pos) {
// Write your code here
unsigned char mask_nible = (1<<4)-1; // o 0x0F
if (pos == 1){
reg =(reg >> 4)& mask_nible;
return reg;
}else{
reg =reg & mask_nible;
return reg;
}
}
int main() {
unsigned char reg;
int pos;
scanf("%hhu %d", ®, &pos);
printf("%d", extractNibble(reg, pos));
return 0;
}