#include <stdio.h>
#include <stdint.h>
uint8_t extract_field(uint16_t reg) {
// Your logic here
/*reg = reg >>4;
uint16_t mask = (1ULL << 5) - 1;
return reg & mask;*/
return (reg >>4) & 0x1F;
}
int main() {
uint16_t reg;
scanf("%hx", ®);
printf("%u", extract_field(reg));
return 0;
}