#include <cstdio>
#include <iostream>
#include <string>
#include <sstream>
#include <stack>
#include <algorithm>
#include <cmath>
#include <queue>
#include <map>
#include <set>
#include <cstdlib>
#include <bitset>
#include <tuple>
#include <assert.h>
#include <deque>
#include <bitset>
#include <iomanip>
#include <limits>
#include <chrono>
#include <random>
#include <array>
#include <unordered_map>
#include <functional>
#include <complex>

template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; }
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; }

const long long MAX = 5100000;
const long long INF = 1LL << 60;
const long long MOD
= 1000000007LL;
//const long long mod = 998244353LL;

using namespace std;
typedef unsigned long long ull;
typedef long long ll;



int main()
{
	/*
	cin.tie(nullptr);
	ios::sync_with_stdio(false);
	*/
	ll n; scanf("%lld", &n);
	vector<ll> y(n); for (ll i = 0; i < n; i++) scanf("%lld", &y[i]);
	long double sum_x = n * (n - 1) / 2;
	long double sum_y = 0;
	long double sum_xy = 0;
	long double sum_x2 = 0;
	long double sum_y2 = 0;
	for (ll i = 0; i < n; i++) {
		sum_y += y[i];
		sum_xy += i * y[i];
		sum_x2 += i * i;
		sum_y2 += y[i] * y[i];
	}
	long double a = (n * sum_xy - sum_x * sum_y) / (n * sum_x2 - sum_x * sum_x);
	long double b = (sum_x2 * sum_y - sum_xy * sum_x) / (n * sum_x2 - sum_x * sum_x);

	long double cost = 0.0;
	for (ll i = 0; i < n; i++) {
		long double req = a * i + b;
		cost += (req - y[i]) * (req - y[i]);
	}
	cout << fixed << setprecision(12) << a + b << " " << a << "\n" << cost << endl;

	return 0;
}