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 11.0.6) (judge verdict: Accepted)

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

class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		final int N = sc.nextInt();
		BigInteger ans = new BigInteger("1");
		final BigInteger TEN_EIGHTEEN = new BigInteger("1000000000000000000");
		final BigInteger ZERO = new BigInteger("0");
		final BigInteger OVER = new BigInteger("-1");
		String[] s = new String[N];
		Boolean flag_z = false;
		for (int i = 0; i < N; ++i) {
			s[i] = sc.next();
			if (s[i].equals("0")) {
				flag_z = true;
			}
		}
		if (flag_z) {
			ans = ZERO;
		} else {
			for (int i = 0; i < N; ++i) {
				BigInteger A = new BigInteger(s[i]);
				if (A.compareTo(ZERO) != 0) {
					if (ans.multiply(A).compareTo(TEN_EIGHTEEN) <= 0) {
						ans = ans.multiply(A);
					} else {
						ans = OVER;
						break;
					}
				} else {
					ans = ZERO;
					break;
				}
			}
		}
		// System.out.println(" "+ans.toString());
		sc.close();
		if (ans.compareTo(ZERO) == -1) {
			System.out.println("-1");
		}else{
			System.out.println(ans.toString());
		}
	}
}