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 Go (1.14.1) (judge verdict: Accepted)

package main

import (
	"bufio"
	. "fmt"
	"io"
	"math/big"
	"os"
)

// github.com/EndlessCheng/codeforces-go
func run(_r io.Reader, _w io.Writer) {
	in := bufio.NewReader(_r)
	out := bufio.NewWriter(_w)
	defer out.Flush()

	var n int
	Fscan(in, &n)
	a := make([]int, n)
	for i := range a {
		Fscan(in, &a[i])
		if a[i] == 0 {
			Fprintln(out, 0)

			return
		}
	}
	s := big.NewInt(1)
	upper := big.NewInt(1e18)
	for _, v := range a {

		s.Mul(s,big.NewInt(int64(v)))
		if s.Cmp( upper)>0 {
			Fprintln(out, -1)
			return
		}
	}
	Fprintln(out, s.Int64())
}

func main() { run(os.Stdin, os.Stdout) }