#include <stdio.h>
#include <stdint.h>
#include <math.h>
uint8_t extract_field(uint16_t reg) {
// Your logic here
uint16_t mask = ((uint16_t)pow(2,5) - 1) << 4;
reg = (reg & mask)>>4;
return uint8_t(reg);
}
int main() {
uint16_t reg;
scanf("%hx", ®);
printf("%u", extract_field(reg));
return 0;
}