import java.math.BigInteger;
import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        BigInteger[] a = new BigInteger[n];
        BigInteger aa = new BigInteger("1000000000000000000");
        BigInteger sum = new BigInteger("1");
        boolean flg = false;
        for (int i = 0; i < n; i++) {
            a[i] = sc.nextBigInteger();
            if(a[i].equals(BigInteger.ZERO)) {
                flg = true;
            }
        }
        if(flg) {
            System.out.println(0);
            return;
        }
        for (int i = 0; i < n; i++) {
            sum = sum.multiply(a[i]);
            if(sum.compareTo(aa) > 0) {
                System.out.println(-1);
                return;
            }
        }
        System.out.println(sum);
    }
}
/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