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 C# (Mono-mcs 6.8.0.105) (judge verdict: Accepted)

using System;
using System.Collections.Generic;
using System.Linq;
class b{
  public static void Main(){
    long n = long.Parse(Console.ReadLine());
    long[] num = Console.ReadLine().Split(' ').Select(s => long.Parse(s)).ToArray();
    Array.Sort(num);
    long max = (long)Math.Pow(10,18);
    long ans = 1;
    for(long i=0; i<n; i++){
      if((double)max/num[i] < (double)ans){
        ans = -1;
        break;
      }
      ans *= num[i];
      if(ans > max){
        ans = -1;
        break;
      }
    }
    Console.WriteLine(ans);
  }
}