#include<stdio.h>

int main(void) {
	long int N;
	int num = 1;
	int sum;
	int count=0;
	scanf("%ld", &N);
	while (N >= num * 2) {
		num *= 2;
		count++;
	}
	sum = num;
	for (; N - sum > 0; num--) {
		while (N - (sum + num * 2) >= 0) {
			sum += num * 2;
			count++;
		}
	}

	printf("%d", count);

}