n = int(input())
A = list(map(int, input().split()))

Sxx = sum([i**2 for i in range(n)])
Sx =  sum([i for i in range(n)])
Sy = sum([a for a in A])
Sxy = sum([i*a for i,a in enumerate(A)])

d = (n*Sxy-Sx*Sy)/(n*Sxx-Sx**2)
b = (Sxx*Sy-Sxy*Sx)/(n*Sxx-Sx**2)
c = sum([(a-d*i-b)**2 for i, a in enumerate(A)])
print(b, d)
print(c)