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)

fun main() = Thread(null, ::abc169b, "(^o^)", 128 * 1024 * 1024).apply { start() }.join()

@OptIn(ExperimentalStdlibApi::class)
fun abc169b() {
    readLine()
    val aList = readLine()!!.split(' ').map { it.toLong() }

    if (0L in aList) return println(0)

    val cap = pow(10L, 18)

    val answer = runCatching {
        aList.fold(1L) { acc, l -> Math.multiplyExact(acc, l) }
    }.fold({ it }, { Long.MAX_VALUE }).takeIf { it <= cap } ?: -1

    println(answer)
}

private fun pow(n: Long, p: Long): Long {
    var x = n
    var y = p
    var result = 1L
    while (y > 0) {
        if (y % 2 == 1L)
            result = (result * x)
        y = y shr 1
        x = (x * x)
    }
    return result
}