#include <stdio.h>
#include <stdint.h>
uint8_t count_set_bits(uint8_t reg) {
// Your code here
int counter = 0;
for(int i=0;i<8;i++) {
if(reg & (1<<i)) counter++;
}
return counter;
}
int main() {
uint8_t reg;
scanf("%hhu", ®);
printf("%u", count_set_bits(reg));
return 0;
}