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 1.8.0) (judge verdict: Wrong Answer)

import java.util.*;
public class Main{
	public static void main(String args[]){
		Scanner sc = new Scanner(System.in);
		int N = sc.nextInt();
		long[] A = new long[N];
		long ans = 1;
		int keta = 1;
		int ansKeta = 1;
		for(int i = 0;i < N;i++){
			A[i] = sc.nextLong();
			keta = (int)Math.floor(Math.log10((double)A[i]));
			if(A[i] == 0){
				ans = 0;
				break;
			}else if(ansKeta + keta < 19 && ansKeta + keta > -1){
				ans *= A[i];
				ansKeta = (int)Math.floor(Math.log10((double)ans));
			}else{
				ans = -1;
				break;
			}
		}
		if(ans > 1000000000000000000L){
			ans = -1;
		}
		System.out.println(ans);
	}
}