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 Scala (2.13.1) (judge verdict: Accepted)

import java.util.Scanner

object Main {
  def main(args: Array[String]): Unit = {
    val sc = new Scanner(System.in)
    val n = sc.nextInt()
    val a = Vector.fill(n)(BigInt(sc.nextBigInteger()))

    val l = BigInt.apply("1000000000000000000")
    if (a.contains(BigInt(0))) {
      println(0)
    } else if (a.count(_ > l) > 0) {
      println(-1)
    } else {
      println(loop(0, BigInt(1)))
    }

    def loop(i: Int, s: BigInt): BigInt = {
      if (s > l) {
        BigInt(-1)
      } else if (i >= n) {
        s
      } else {
        loop(i + 1, s * a(i.toInt))
      }
    }

  }

}