## https://yukicoder.me/problems/no/1816

import heapq

def main():
    N = int(input())

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

    A.sort()

    index = [False] * (2 * N)
    min_queue = []
    max_queue = []
    for i in range(N):
        heapq.heappush(min_queue, (A[i], i))
    for i in range(N):
        heapq.heappush(max_queue, (-A[i], i))

    for turn in range(N - 1):
        if turn % 2 == 0:
            array = []
            while len(array) < 2:
                min_value, min_index = heapq.heappop(min_queue)
                if not index[min_index]:
                    array.append(min_value)
                    index[min_index] = True
            x = array[0] * array[1]
            heapq.heappush(min_queue, (x, N + turn))
            heapq.heappush(max_queue, (-x, N + turn))
        else:
            array_count = 0
            while array_count < 2:
                _, max_index = heapq.heappop(max_queue)
                if not index[max_index]:
                    array_count += 1
                    index[max_index] = True
            heapq.heappush(min_queue, (1, N + turn))
            heapq.heappush(max_queue, (-1, N + turn))

    while len(min_queue) > 0:
        min_value, min_index = heapq.heappop(min_queue)
        if not index[min_index]:
            print(min_value)
            break


if __name__ == "__main__":
    main()