import sys
input = sys.stdin.readline

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

if N==1:
    print(A[0])
elif N==2:
    print(A[0]*A[1])
elif N%2==1:
    print(1)
elif N>=5:
    print(1)
elif N==4:
    B=sorted(A)
    C=[B[0]*B[1],B[2],B[3]]
    C.sort()
    print(C[0])