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 C (Clang 10.0.0) (judge verdict: Wrong Answer)

#include <stdio.h>

int main(void) {
	int N = 0;
	unsigned long int a[100000] = { 0 };
	unsigned long int ans = 1;

	scanf("%d", &N);

	for (int i = 0; i < N; i++) {
		scanf("%lu", &a[i]);
		if (a[i] == 0) {
			printf("0");
			return 0;
		}
	}

	for (int i = 0; i < N; i++) {
		ans = ans * a[i];
		if (ans > 1000000000000000000) {
			printf("-1");
			return 0;
		}
	}
	printf("%lu", &ans);

	return 0;
}