#include <bits/stdc++.h>
//#include <atcoder/all>
using namespace std;
//using namespace atcoder;
//using mint = modint1000000007;
//const int mod = 1000000007;
//using mint = modint998244353;
//const int mod = 998244353;
//const int INF = 1e9;
//const long long LINF = 1e18;
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define rep2(i,l,r)for(int i=(l);i<(r);++i)
#define rrep(i, n) for (int i = (n) - 1; i >= 0; --i)
#define rrep2(i,l,r)for(int i=(r) - 1;i>=(l);--i)
#define all(x) (x).begin(),(x).end()
#define allR(x) (x).rbegin(),(x).rend()
#define P pair<int,int>
template<typename A, typename B> inline bool chmax(A & a, const B & b) { if (a < b) { a = b; return true; } return false; }
template<typename A, typename B> inline bool chmin(A & a, const B & b) { if (a > b) { a = b; return true; } return false; }

int main() {
	std::ios::sync_with_stdio(false);
	std::cin.tie(nullptr);
	int n; cin >> n;
	vector<int>a(n);
	rep(i, n)cin >> a[i];
	sort(all(a));
	auto f = [&](int x, int y)->int {
		return x < 0 and y < 0 ? -x - y : abs(x - y);
	};
	long long ans = 0;
	if (a.front() > 0) {// all sei
		ans = a.back() - a.front();
	}
	else if (a[1] > 0) {// hu one
		rep(i, n - 1)ans += f(a[i], a[i + 1]);
	}
	else if (a.back() < 0) {// all hu
		rep(i, n)ans -= 2 * a[i];
		ans += a[0] + a[1];
	}
	else {
		vector<int>b;
		b.push_back(a[0]);
		rep2(i, 2, n)b.push_back(a[i]);
		b.push_back(a[1]);
		rep(i, n - 1)ans += f(b[i], b[i + 1]);
	}
	cout << ans << endl;
	return 0;
}