#include <stdio.h>
#include <stdint.h>
uint8_t extract_field(uint16_t reg) {
// Your logic here
uint16_t val = 0;
val =( reg >> 4 ) & 0x1F;
if(val > 31)
{
val &= 0x1F;
}
return val;
}
int main() {
uint16_t reg;
scanf("%hx", ®);
printf("%u", extract_field(reg));
return 0;
}