#include <bits/stdc++.h>
#define FOR(I,X,Y) for(int (I)=(X);(I)<(Y);(I)++)
#define REP(I,X,Y) for(int (I)=(Y)-1;(I)>=(X);(I)--)
#define ALL(X) (X).begin(),(X).end()
#define INF 1000000007
#define LINF 1000000000000000007
typedef long long ll;
using namespace std;

int main(){
  int N;
  cin >> N;
  double xy=0,x=0,y=0,x2=0,n=N,cost=0;
  double a,b,A[N];
  FOR(i,0,N){
    cin >> A[i];
    x += i;
    x2 += i*i;
    y += A[i];
    xy += i*A[i];
  }
  a = (n*xy - x*y)/(n*x2-x*x);
  b = (x2*y - xy*x)/(n*x2-x*x);
  FOR(i,0,N){
    cost += pow((A[i]-b-a*i),2);
  }
  cout << fixed << setprecision(10) << b << ' ' << a << endl << cost;
}