N=int(input())
S=input()
S=S.rstrip().split(" ")
list1=[]
for i in range(N):
    list1.append(int(S[i]))
#print(list1)
ans=list1[0]
for j in range(1,N):
    if ans==0:
        list2=[ans+list1[j],ans-list1[j],ans*list1[j]]
        ans=max(list2)
    else:
        list2=[ans+list1[j],ans-list1[j],ans*list1[j],int(ans/list1[j])]
        ans=max(list2)
print(ans)