import java.math.BigDecimal;
import java.util.*;

public class Main {

    static BigDecimal MAX = new BigDecimal(1_000_000_000_000_000_000L);
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        long[] a = new long[n];
        for (int i = 0; i < n; i++) {
            a[i] = sc.nextLong();
            if(a[i] == 0) {
            	System.out.println(0);
            	return;
            }
        }
        BigDecimal d = new BigDecimal(a[0]);
        for (int i = 1; i < n; i++) {
            d = d.multiply(new BigDecimal(a[i]));
            if(d.compareTo(MAX) == 1){
            	System.out.println(-1);
            	return;                
            }
        }
        System.out.println(d.longValue());
        
        sc.close();

    }

}

/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