#include <bits/stdc++.h>
using namespace std;
bool v[1100];
int main()
{
    int n;
    scanf("%d", &n);
    memset(v, 0, sizeof(v));
    
    int t = n, d = 0;
    while (t >= 3)
    {
        int mi = 0;
        if (d == 0)
        {
            for (int i = 1; i <= n; i++)
            {
                if (v[i] == 0)
                {
                    mi++;
                    if (mi == 3)
                        mi = 0, v[i] = 1, t--;
                }
            }
        }
        else
        {
            for (int i = n; i >= 1; i--)
            {
                if (v[i] == 0)
                {
                    mi++;
                    if (mi == 3)
                        mi = 0, v[i] = 1, t--;
                }
            }
        }
        d = 1 - d;
    }
    if (d == 0)
    {
        for (int i = 1; i <= n; i++)
            if (v[i] == 0)
            {
                printf("%d\n", i);
                return 0;
            }
    }
    else
    {
        for (int i = n; i >= 1; i--)
            if (v[i] == 0)
            {
                printf("%d\n", i);
                return 0;
            }
    }
    return 0;
}