Problem:
Score : 200 points

Problem Statement

Given N integers A_1, ..., A_N, compute A_1 \times ... \times A_N.

However, if the result exceeds 10^{18}, print -1 instead.

Constraints

2 \leq N \leq 10^5

0 \leq A_i \leq 10^{18}

All values in input are integers.

Input

Input is given from Standard Input in the following format:

N
A_1 ... A_N

Output

Print the value A_1 \times ... \times A_N as an integer, or -1 if the value exceeds 10^{18}.

Sample Input 1

2
1000000000 1000000000

Sample Output 1

1000000000000000000

We have 1000000000 \times 1000000000 = 1000000000000000000.

Sample Input 2

3
101 9901 999999000001

Sample Output 2

-1

We have 101 \times 9901 \times 999999000001 = 1000000000000000001, which exceeds 10^{18}, so we should print -1 instead.

Sample Input 3

31
4 1 5 9 2 6 5 3 5 8 9 7 9 3 2 3 8 4 6 2 6 4 3 3 8 3 2 7 9 5 0

Sample Output 3

0

Solution in Common Lisp (SBCL 2.0.3) (judge verdict: Time Limit Exceeded)

(defun mult-all (n a)
  (let ((res 1))
	(dotimes (i n)
	  (if (zerop (aref a i) )
		  (setf res 0)
		  (setf res (* res (aref a i)))))
	(if (> res 1000000000000000000)
		(setf res -1))
	res))

(defun create-data ()
  (let* ((n (read))
         (a (make-array `(,n) :element-type 'integer)))
    (dotimes (i n)
      (setf (aref a i) (read)))
    (values n a)))

(multiple-value-bind (n a) (create-data)
  (format t "~A~%" (mult-all n a)))