
import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;

public class Main {

  final static Long MAX = 1000000000000000000L;

  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    int n = sc.nextInt();
    sc.nextLine();
    List<Long> l = new ArrayList<Long>();
    for(int i = 0;i < n;i++) {
      l.add(sc.nextLong());
    }
    sc.close();

    if(l.contains(0L)) {
      System.out.println(0);
    }else {

      Long sum = 1L;

      for(Long l2:l) {
        if(sum > MAX/l2) {
          System.out.println(-1);
          return;
        }
        sum *= l2;
      }
      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