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.io.FileNotFoundException;
import java.util.Scanner;

public class Main {
    public static void main(String[] args) throws FileNotFoundException {

//    	File file = new File("src/in.txt");

        //コード
//    	Scanner sc = new Scanner(file);
    	Scanner sc = new Scanner(System.in);

    	int N = sc.nextInt();

    	long[] A = new long[N];

    	long times = 1;
    	long K = (long) Math.pow(10,18);

    	boolean flg = true;
    	boolean haszero = false;

    	for(int i=0;i<N;i++) {
    		A[i]=sc.nextLong();
    	}

    	for(int i=0;i<N;i++) {
    		if(A[i]==0) {
    			haszero = true;
    			break;
    		}
    	}

    	if(haszero==false) {

        	for(int i=0;i<N;i++) {
        		times = times * A[i];

        		if(times>K) {
        			flg = false;
        			break;
        		}
        	}

        	if(flg) {
        		System.out.println(times);
        	} else {
        		System.out.println("-1");
        	}

    	} else {
    		System.out.println("0");
    	}
    }
}