#include <stdio.h>
#include <stdint.h>
uint8_t extract_field(uint16_t reg) {
// Your logic here
uint16_t skip=reg;
for(char i=0;i<=4;i++){
skip=(reg>>i);
}
if(skip>60){
return skip>>1;
}else
return skip;
}
int main() {
uint16_t reg;
scanf("%hx", ®);
printf("%u", extract_field(reg));
return 0;
}