#include <stdio.h>
#include <stdint.h>
int bit,cnt;
uint8_t count_set_bits(uint8_t reg) {
// Your code here
cnt=0;
for(bit=7;bit>=0;bit--)
{
if(reg & (1<<bit))
{
cnt++;
}
}
return cnt;
}
int main() {
uint8_t reg;
scanf("%hhu", ®);
printf("%u", count_set_bits(reg));
return 0;
}