import numpy as np
N = int(input())
y = list(map(int, input().split()))
x = [i for i in range(N)]


def least_squares(x, y):
    n = len(x)
    var_x = np.var(x)
    mu_x = np.mean(x)
    mu_y = np.mean(y)
    cov = sum((x-mu_x)*(y-mu_y)) / n
    a = cov / var_x
    b = mu_y - a*mu_x
    cost = sum((_y - a*_x - b) ** 2 for _x, _y in zip(x, y))
    return a, b, cost


a, b, c = least_squares(x, y)
print(b, a)
print(c)