import static java.lang.Math.multiplyExact;
import java.util.Arrays;
import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        Integer n = scanner.nextInt();
        Long[] a = new Long[n];
        Long limit = (long)Math.pow(10,18);

        for (int i = 0; i < n; i++) {
            a[i] = scanner.nextLong();
        }

        Arrays.sort(a);

        if (a[0] == 0){
            System.out.print(0);
            System.exit(0);
        }

        Long result = a[0];

        for (int i = 1; i < n; i++) {
            try {
                result = multiplyExact(result,a[i]);
            } catch (Exception e) {
                System.out.print(-1);
                System.exit(0);
            }
            if (result > limit) {
                System.out.print(-1);
                System.exit(0);
            }
        }
        System.out.print(result);
    }
}

/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz