import java.util.*;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int time = sc.nextInt();
        long ans = 1L;
        long std = 1000000000000000000L;
        for (int i = 0; i < time; i++) {
            long mul = sc.nextLong();
            if(mul == 0){
                System.out.println(0);
                return;
            }else if(ans == -1){
                continue;
            }else if(mul > std / ans){
                ans = -1;
            }else{
                ans *= mul;
            }
        }
        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