n = int(input()) li = list(map(int, input().split())) dp = [[x for x in li] for _ in range(2)] for i in range(1, n): dp[0][i] = max(dp[0][i - 1] + li[i], dp[0][i]) dp[1][i] = max(dp[0][i - 1], dp[1][i - 1] + li[i]) print(max(max(dp[0]), max(dp[1]))) dp