import sys

sys.setrecursionlimit(200005)
# sys.set_int_max_str_digits(200005)
int1 = lambda x: int(x)-1
pDB = lambda *x: print(*x, end="\n", file=sys.stderr)
p2D = lambda x: print(*x, sep="\n", end="\n\n", file=sys.stderr)
def II(): return int(sys.stdin.readline())
def LI(): return list(map(int, sys.stdin.readline().split()))
def LLI(rows_number): return [LI() for _ in range(rows_number)]
def LI1(): return list(map(int1, sys.stdin.readline().split()))
def LLI1(rows_number): return [LI1() for _ in range(rows_number)]
def SI(): return sys.stdin.readline().rstrip()

dij = [(0, 1), (-1, 0), (0, -1), (1, 0)]
# dij = [(0, 1), (-1, 0), (0, -1), (1, 0), (1, 1), (1, -1), (-1, 1), (-1, -1)]
# inf = -1-(-1 << 31)
inf = -1-(-1 << 62)

md = 10**9+7
# md = 998244353

def mul(aa,s):
    res=1
    for i,a in enumerate(aa):
        if s>>i&1:res*=a
    return res

n=II()
aa=LLI(n)
mxs=[]
for s in range(64):
    mx=1
    for a in aa:mx=max(mx,mul(a,s))
    mxs.append(mx)

dp=[1]*64
for _ in range(4):
    for t in range(64)[::-1]:
        for s, mx in enumerate(mxs):
            if s&t:continue
            dp[s|t]=max(dp[s|t],dp[t]*mx)
print(dp[-1])