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 Java (OpenJDK 1.8.0) (judge verdict: Time Limit Exceeded)

import java.util.*;
import java.math.*;

public class Main {

  public static void main (String[] args) {
    Scanner sc = new Scanner(System.in);
    int N = sc.nextInt();
    BigDecimal[] A = new BigDecimal[N+1];
    BigDecimal a = new BigDecimal(1);
    BigDecimal b = new BigDecimal(Math.pow(10,18));
    for (int i =1; i<=N; i++) {
      A[i] = sc.nextBigDecimal();
      a = a.multiply(A[i]);
      if (i == N) {
        if (a.compareTo(b) > 0) {
        a = new BigDecimal(-1);
        break;
        }
      }
    }
    System.out.println(a);
  }
}