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 Kotlin (1.3.71) (judge verdict: Accepted)

import java.lang.Math.pow
import java.math.BigInteger

private fun readLn() = readLine()!! // string line
private fun readInt() = readLn().toInt() // single int
private fun readStrings() = readLn().split(" ") // list of strings
private fun readInts() = readStrings().map { it.toInt() } // list of ints

private fun readLong() = readLn().toLong() // single int
private fun readLongs() = readStrings().map { it.toLong() }

fun main(){
    val n = readInt()
    val numList = readLongs()

    //var ans: Long = 1
    var ans: BigInteger = BigInteger.valueOf(1)
    val limit: Long = pow(10.0, 18.0).toLong()

    if(numList.contains(0)){
        ans = BigInteger.valueOf(0)
    }else{
        for(i in numList){
            ans *= BigInteger.valueOf(i)
            if(ans > BigInteger.valueOf(limit)){
                ans = BigInteger.valueOf(-1)
                break
            }
        }
    }

    println(ans)
}