import java.util.*;

public class Main {
    public static void main(String[] args) throws Exception {
        Scanner sc = new Scanner(System.in);
        int N = Integer.parseInt(sc.next());
        long sum = 1;
        for(int i=0; i<N; i++) {
            long next = Long.parseLong(sc.next());
            if(next == 0) {
                sum = 0;
                break;
            }
            if(sum != -1) {
                if(1000000000000000000L / next < sum) {
                    sum = -1;
                }else {
                    sum *= next;
                }
            }else {
                continue;
            }
        }
        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