import java.util.Scanner;
public class Main {
	public static void main(String[] args)throws Exception{
		Scanner stdIn=new Scanner(System.in);
		int N=stdIn.nextInt();
		long A[]=new long[N];
		for(int i=0;i<N;i++){
			A[i]=stdIn.nextLong();
			if(A[i]==0){
				System.out.println(0);
				System.exit(0);
			}
		}
		try{
			long sum=1,key=1;
			key*=Math.pow(10,9);
			key*=Math.pow(10,9);
			for(int i=0;i<N;i++){
				sum=Math.multiplyExact(sum,A[i]);
			}
			if(sum>key)
				System.out.println(-1);
			else
				System.out.println(sum);
		}
		catch(Exception e){
			System.out.println(-1);
		}
	}
}

/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