#include<stdio.h>
int main()
{
	int x;
	scanf("%d", &x);
	int ans, now, i;
	int dx[7] = { 2,2,-1,-1,2,-1,-1 };
	ans = now = 0;
	for (i = 0;; i = (i + 1) % 7)
	{
		now += dx[i];
		if (dx[i] < 0)
			ans -= dx[i];
		else
			ans += dx[i];
		if (now == x)
			break;
	}
	printf("%d", ans);
	return 0;
}