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

int Min, N, *Progression;

void Search(int, int);
int BitNumber(int);

int main(int argc, const char * argv[])
{
    scanf("%d", &N);
    Min = N;
    Progression = (int*)malloc(sizeof(int) * (N + 1));
    
    for (int i=0; i <= N; i++)
        Progression[i] = 0;

    Search(1, 1);
    
    if (Min == N)
        printf("%d", -1);
    else
        printf("%d", Min);

    return EXIT_SUCCESS;
}

void Search(int level, int count)
{
    if (level == N)
    {
        if (Min > count)
            Min = count;
    }
    else if (level > 0 && level <= N && Progression[level] == 0)
    {
        Progression[level] = -1;
        Search(level + BitNumber(level), count + 1);
        Search(level - BitNumber(level), count + 1);
    }
}

int BitNumber(int a)
{
    int temp = 0;
    
    do
    {
        temp += a % 2;
        a /= 2;
    } while (a > 0);
    
    return temp;
}