N = int(input())
A = list(map(int,input().split()))
dp = [[-1 for _ in range(N+1)] for _ in range(100)]
dp[0][0] = 1000
for n in range(1,N):
    for i in range(250):
        # n日目
        for j in range(250):
        # n-1日目
            if dp[j][n-1] != -1:
                dp[i][n] = max(dp[j][n-1]+(j-i)*A[n-1],dp[i][n])
ans = 1000
for i in range(20):
    if dp[i][-2] != -1:
        if dp[i][-2]+i*A[-1] > ans:
            ans = dp[i][-2]+i*A[-1]
print(ans)