import heapq

N = int(input())

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

q = []

for i in A:
    heapq.heappush(q,-i)

for i in range(N-1):

    v = -1 * heapq.heappop(q)
    w = -1 * heapq.heappop(q)

    if i % 2 == 0:
        heapq.heappush(q, -1 * v*w)
    else:
        heapq.heappush(q,-1)

print (-1 * q[0])