## https://yukicoder.me/problems/no/3129

MAX_VALUE = 10 ** 18

MIN_VALUE = - 10**18
         

def main():
    N = int(input())
    A = list(map(int, input().split()))

    # forward
    forward_cum_list = [0] * (N + 1)
    for i in range(N):
        forward_cum_list[i + 1] = A[i] + forward_cum_list[i]

    # maxの計算
    forward_max_list = [0] * N
    min0 = forward_cum_list[0]
    for i in range(N):
        f = forward_cum_list[i + 1]    
        forward_max_list[i] = f - min0
        min0 = min(min0, forward_cum_list[i])
    
    # minの計算
    forward_min_list = [0] * N
    max0 = forward_cum_list[0]
    for i in range(N):
        f = forward_cum_list[i + 1]    
        forward_min_list[i] = f - max0
        max0 = max(max0, forward_cum_list[i])
    
    # backward
    backward_cum_list = [0] * (N + 1)
    for i in reversed(range(N)):
        backward_cum_list[i] = A[i] + backward_cum_list[i + 1]
    
    backward_max_list = [0] * N
    min0 = backward_cum_list[-1]
    for i in reversed(range(N)):
        b = backward_cum_list[i]
        backward_max_list[i] = b - min0
        min0 = min(min0, backward_cum_list[i])

    backward_min_list = [0] * N
    max0 = backward_cum_list[-1]
    for i in reversed(range(N)):
        b = backward_cum_list[i]
        backward_min_list[i] = b - max0
        max0 = max(max0, backward_cum_list[i])
    
    # backwardの累積min, max
    backward_cum_max_list = [MIN_VALUE] * N
    backward_cum_max = MIN_VALUE
    backward_cum_min_list = [MAX_VALUE] * N
    backward_cum_min = MAX_VALUE

    for i in reversed(range(N)):
        backward_cum_max = max(backward_cum_max, backward_max_list[i])
        backward_cum_min = min(backward_cum_min, backward_min_list[i])
        backward_cum_max_list[i] = backward_cum_max
        backward_cum_min_list[i] = backward_cum_min

    answer = MIN_VALUE
    forward_cum_max = MIN_VALUE
    forward_cum_min = MAX_VALUE
    for i in range(1, N):
        forward_cum_max = max(forward_cum_max, forward_max_list[i - 1])
        forward_cum_min = min(forward_cum_min, forward_min_list[i - 1])

        answer = max(answer, forward_cum_max * backward_cum_max_list[i])
        answer = max(answer, forward_cum_min * backward_cum_min_list[i])
    
    print(answer)




if __name__ == "__main__":
    main()