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: Wrong Answer)

object Main extends App {
	val pw = new java.io.PrintWriter(System.out)

	@scala.annotation.tailrec
	def loop(start: Int, end: Int)(f: Int => Unit): Unit =
		if (start < end) {
			f(start)
			loop(start + 1, end)(f)
		}

	val n = Scanner.nextInt
	var a = 1L
	var flag = true

	loop(0, n) { i =>
		a = a * Scanner.nextLong
		flag = a <= 1000000000000000000L
	}

	pw.println(if (flag) a else -1)
	pw.flush()
}

object Scanner {
	private val buf = new Array[Byte](1024); private var ptr = 0; private var len = 0

	@inline private def isPrintableChar(c: Int): Boolean = 33 <= c && c <= 126
	@inline private def hasNextByte(): Boolean = if (ptr >= len) { ptr = 0; len = System.in.read(buf); len > 0 } else true
	@inline private def hasNext(): Boolean = {
		while (hasNextByte() && !isPrintableChar(buf(ptr))) ptr += 1
		hasNextByte()
	}
	@inline private def readByte(): Byte = if (hasNextByte()) { val res = buf(ptr); ptr += 1; res } else -1

	def next(): String = {
		if(!hasNext()) ???
		val sb = new StringBuilder; var b = readByte()
		while (isPrintableChar(b)) { sb.append(b.toChar); b = readByte() }
		sb.toString
	}

	def nextInt(): Int = {
		val n = nextLong()
		if (n < Int.MinValue || Int.MaxValue < n) ???
		n.toInt
	}

	def nextLong(): Long = {
		if(!hasNext()) ???
		var minus = false; var b = readByte()
		if (b == '-') { minus = true; b = readByte() }

		@scala.annotation.tailrec
		def go (b: Byte, n: Long = 0): Long = if ('0' <= b && b <= '9') go(readByte(), n * 10 + b - '0') else if (minus) -n else n

		go(b)
	}

	def nextDouble(): Double = next().toDouble
}