#include"bits/stdc++.h"
#include"atcoder/all"
using namespace std;
using namespace atcoder;
#pragma GCC target("avx2")
#pragma GCC optimize("O2")
#pragma GCC optimize("unroll-loops")
using ll = long long;
using ld = long double;
#define rep(i,m,n) for(ll i=(ll)m;i<(ll)n;i++)
#define drep(i,m,n) for(ll i=m-1;i>=n;i--)
#define Endl endl
#define pr(i,j) make_pair(i,j) 
#define isin(x,l,r) (l<=x&&x<r)
#define chmin(a,b) a=min(a,b)
#define chmax(a,b) a=max(a,b)
#define srt(ar) sort(ar.begin(),ar.end())
#define rev(ar) reverse(ar.begin(),ar.end())
const ll inf = 1e18;
const ld pi = 3.14159265358979;
using mint = modint998244353;
clock_t ST, FN;
int main() {
	ST = clock();
	ios::sync_with_stdio(false);
	cin.tie(nullptr);

	ll x;
	cin >> x;
	vector<ll>ar = { 2,2,-1,-1,2,-1,-1 };
	ll ans = 0;
	ll now = 0;
	rep(i, 0, 100) {
		rep(j, 0, 7) {
			now += ar[j];
			ans += abs(ar[j]);
			if (now == x) {
				cout << ans << endl;
				return 0;
			}
		}
	}

	//cout << FN - ST << "ms" << endl;
}