import java.util.*;

public class Main {
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    int n = sc.nextInt();
    long ans = 1;
    for(int i = 0; i < n; i++) {
      long a = sc.nextLong();
      if(a == 0) {
        ans = 0;
      } else {
        if(ans <= ((long)Math.pow(10, 18) / a)) {
          if(ans >= 0) ans *= a;
        } else {
          ans = -1;
        }
      }
    }
    System.out.println(ans);
  }
}
/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