#include <cstdio>
#include <climits>
#include <cmath>
#include <iostream>
#include <iomanip>
#include <string>
#include <cstdio>
#include <climits>
#include <iostream>
#include <algorithm>
#include <string>
#include <vector>
#include <utility>
#include <queue>
#include <cstring>
#include <set>
#include <map>
#include <complex>
#define rep(i, n) for (int i = 0; i < int(n); i++)
using namespace std;
long long MOD = 1000000007;
long long INF = 1000000000000000; //10^15
typedef long long ll;
typedef unsigned long long ull;


ll powMod(ll x, ll n, ll mod) {
  if (n == 0) return 1;
  ll t = powMod(x, n/2, mod);
  t = t * t % mod;
  if (n & 1) return t * x % mod;
  return t;
}

int main(void) {
  
  int n;
  double a[1010];
  cin >> n;
  rep(i, n) cin >> a[i];

  double N = n;

  double aav = 0;
  rep(i, n) aav += a[i];
  aav /= N;

  double y, x;
  rep(i, n) {
    y += (a[i] - aav) * ((double)i - (N + 1.0)/2.0);
  }
  y /= N * (N + 1.0) * (2.0 * N + 1.0)/6.0 - (N * (N + 1.0) * (N + 1.0))/4.0;

  x = aav - y * (N + 1.0) / 2.0;

  cout << setprecision(20) << x + y << " " << setprecision(20) << y << endl;
  double c = 0;
  rep(i, n) {
    double k = a[i] - x - y - (double)i * y;
    c += k * k;
  }
  cout << std::setprecision(20) << c << endl;
}