#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define NODE 1000
#define SIZE 1000

/* Queue */
int path[SIZE][NODE];
int length[SIZE];
int root[NODE];
int ans[2];

int bitCount( int bit);
int search( int start, int goal);
int b_search( int *array, int target, int size);
void quick_sort( int *array, int left, int right);
void change(int &a, int &b);

int main(void)
{
	int n, i;
	scanf("%d", &n);
	search(1, n);

	if(ans[1] != NULL) {
		printf("%d\n", ans[1]+2);
	} else {
		printf("-1");
	}
	return 0;
}

int search(int start, int goal)
{
	int rear = 1, front = 0, root_cnt = 1;
	path[0][0] = start;
	length[0] = 0;
	root[0] = start;

	while( front < rear ) {
		int len = length[front];
		int node = path[front][len];
		int i, bit = bitCount(path[front][len]);

		for( i = 0; i < 2; i++) {
			quick_sort(root, 0, root_cnt-1);
			switch(i) {
			case 0:
				if( b_search(root, path[front][len]+bit, root_cnt) != 1) {
					if( path[front][len]+bit == goal ) {
						if( ans[1] == NULL || ans[1] >len) {
							ans[0] = front;
							ans[1] = len;
						}
					} else if( path[front][len]+bit < goal) {
						root[root_cnt] = path[front][len]+bit;
						root_cnt++;
						int j;
						for( j = 0; j <= len; j++) {
							path[rear][j] = path[front][j];
						}
						path[rear][len+1] = path[front][len]+bit;
						length[rear] = len + 1;
						rear++;
					}
				}
				break;
			case 1:
				if( b_search(root, path[front][len]-bit, root_cnt) != 1
				&& path[front][len] < goal
				&& path[front][len]-bit > 0) {
					root[root_cnt] = path[front][len]-bit;
					root_cnt++;
					int j;
					for( j = 0; j <= len; j++) {
						path[rear][j] = path[front][j];
					}
					path[rear][len+1] = path[front][len]-bit;
					length[rear] = len + 1;
					rear++;
				}
				break;
			}
		}
		front++;
	}


	return 0;
}


int bitCount(int bit)
{
	int cnt = 0;
	for( ; bit != 0; bit>>=1) {
		cnt += bit & 1;
	}

	return cnt;
}

int b_search( int *array, int target, int size)
{
	int min = 0, max = size-1, mid;

	while( min <= max) {
		mid = (min+max)/2;

		if( array[mid] == target) {
			return 1;
		} else if( array[mid] < target) {
			min = mid+1;
		} else if ( array[mid] > target) {
			max = mid-1;
		}
	}
	return NULL;
}

void quick_sort(int *array, int left, int right)
{
	if( left >= right) return;

	int p = left, k = p+1;

	while( k <= right ) {
		if( array[k] < array[left] ) {
			change(array[k], array[p+1]);
			p++;
		}
		k++;
	}
	change(array[left], array[p]);
	quick_sort(array, left, p-1);
	quick_sort(array, p+1, right);
}

void change(int &a, int &b)
{
	int temp = a;
	a = b;
	b = temp;
}