#include "bits/stdc++.h"

using namespace std;

using ll = long long;
using ld = long double;

const double PI = 3.1415926535897932384626433832795;

const int dx[] = { 0, 1, 0, -1 };
const int dy[] = { -1, 0, 1, 0 };

int gcd(int x, int y) { return y ? gcd(y, x % y) : abs(x); }
ll gcd(ll x, ll y) { return y ? gcd(y, x % y) : abs(x); }
int lcm(int x, int y) { return x / gcd(x, y) * y; }
ll lcm(ll x, ll y) { return x / gcd(x, y) * y; }

pair<double, double> f(const vector<pair<int, int>> &v) {
	int n = v.size();

	double x = 0, y = 0, xx = 0, xy = 0;
	for (int i = 0; i < n; i++) {
		x += v[i].first;
		y += v[i].second;
		xx += v[i].first * v[i].first;
		xy += v[i].first * v[i].second;
	}

	double a = (n * xy - x * y) / (n * xx - x * x);
	double b = (xx * y - xy * x) / (n * xx - x * x);

	return { a, b };
}

int main() {
	//ios::sync_with_stdio(false);
	//cin.tie(0);

	int n;
	cin >> n;

	vector<int> a(n);
	for (auto &v : a) {
		cin >> v;
	}

	vector<pair<int, int>> v(n);
	for (int i = 0; i < n; i++) {
		v[i] = make_pair(i, a[i]);
	}

	double aa, bb;
	tie(aa, bb) = f(v);
	printf("%.10f %.10f\n", bb, aa);

	double c = 0;
	for (int i = 0; i < n; i++) {
		double y = aa * i + bb;
		double d = y - a[i];
		c += d * d;
	}

	printf("%.10f\n", c);
	return 0;
}