#include <stdio.h>
#include <stdint.h>
uint8_t count_set_bits(uint8_t reg) {
// Your code here
uint8_t bit = 0;
uint8_t cnt = 0;
for(uint8_t i = 0 ; i < 8; i++)
{
bit = (reg >> i) & 0x01;
if(bit == 1)
{
cnt++;
}
}
return cnt;
}
int main() {
uint8_t reg;
scanf("%hhu", ®);
printf("%u", count_set_bits(reg));
return 0;
}