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