#include <stdio.h>
#include <stdint.h>
uint8_t count_set_bits(uint8_t reg) {
uint8_t count = 0;
if(reg == 0)return 0;
while(reg > 0){
count +=(reg & 1U)?1:0;
reg = reg >>1;
}
return count;
}
int main() {
uint8_t reg;
scanf("%hhu", ®);
printf("%u", count_set_bits(reg));
return 0;
}