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