var
x,w,k,n,i,max:longint;
ans:int64;
begin
readln(n);
max:=-10;
ans:=1;
for i:=1 to n do
begin
readln(x);
if x<>0 then ans:=ans*x else inc(w);
if x<0 then
begin
if max<x then max:=x;
end;
end;
if (ans<0)and(ans<>max) then ans:=ans div max;
if w=n then write(0) else write(ans);
end.