import java.math.BigDecimal;
import java.util.Scanner;

public class Main {

	public static void main(String[] args) {

		Scanner scan = new Scanner(System.in);
		int n = scan.nextInt();
		BigDecimal[] an = new BigDecimal[n];

		for (int i = 0; i < n; i++) {
			BigDecimal a = scan.nextBigDecimal();
			if (BigDecimal.ZERO.compareTo(a) == 0) {
				System.out.println(0);
				System.exit(0);
			}
			an[i] = a;
		}

		BigDecimal ans = BigDecimal.ONE;
		for (int i = 0; i < an.length; i++) {
			ans = ans.multiply(an[i]);
			if (ans.compareTo(BigDecimal.ONE.scaleByPowerOfTen(18)) > 0) {
				System.out.println(-1);
				System.exit(0);
			}
		}

		if (ans.compareTo(BigDecimal.ONE.scaleByPowerOfTen(18)) <= 0) {
			System.out.println(ans);
		} else {
			System.out.println(-1);
		}

		scan.close();
	}

}

/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