from math import sqrt, log2

n = int(input())
P = [int(input()) for _ in range(n)]

Fn = sqrt(19 * (1 - 0.81**n)) / (19 * (1 - 0.9**n))
F_ = sqrt(19) / 19
fn = 1200 * (Fn - F_) / (1 - F_)
res = 0.0
for i in range(n):
    res += 2**(P[i] / 800) * 0.9**(i + 1)
ans = 800 * log2(res / (9 * (1 - 0.9**n))) - fn
print(int(ans))