import java.util.*;

public class Main{
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        long result = 1;

        for (int i=0;i<n;i++){
            long input = sc.nextLong();
            if (input == 0) { result = 0; break;}

            if (result > 1000000000000000000L/input || result == -1) {
                result = -1;
            } else {
                result = result * input;
            }
        }

        System.out.println(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