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 (
	"fmt"
	"math"
)

func main() {
	var n int
	fmt.Scan(&n)

	var (
		ans  int64 = 1
		a    int64
		over bool = false
		zero bool = false
	)

	for i := 0; i < n; i++ {
		fmt.Scan(&a)

		if a >= math.MaxInt64/ans {
			over = true
		}
		if a == 0 {
			zero = true
		}
		if !over && !zero {
			ans *= a
		}
		if ans > 1e18 {
			over = true
		}
	}

	if zero {
		fmt.Println(0)
	} else if over {
		fmt.Println(-1)
	} else {
		fmt.Println(ans)
	}
}