using System.Linq;
using System;

public class Hello
{
    public static void Main()
    {
        var n = int.Parse(Console.ReadLine().Trim());
        string[] line = Console.ReadLine().Trim().Split(' ');
        var a = Array.ConvertAll(line, long.Parse);
        var max = a[0]; var min = a[0];
        for (int i = 1; i < n; i++)
        {
            var tmax = getMax(max, min, a[i]);
            var tmin = getMin(max, min, a[i]);
            max = tmax;
            min = tmin;
        }
        Console.WriteLine(max);
    }
    public static long getMin(long a1, long a2, long b)
    {
        var w = new long[8];
        w[0] = a1 * b;
        w[1] = a1 + b;
        w[2] = a1 - b;
        w[3] = a2 * b;
        w[4] = a2 + b;
        w[5] = a2 - b;
        if (b != 0)
        {
            w[6] = a1 / b;
            w[7] = a2 / b;
        }
        else
        {
            w[6] = long.MaxValue;
            w[7] = long.MaxValue;
        }
        return w.Min();
    }
    public static long getMax(long a1, long a2, long b)
    {
        var w = new long[8];
        w[0] = a1 * b;
        w[1] = a1 + b;
        w[2] = a1 - b;
        w[3] = a2 * b;
        w[4] = a2 + b;
        w[5] = a2 - b;
        if (b != 0)
        {
            w[6] = a1 / b;
            w[7] = a2 / b;
        }
        else
        {
            w[6] = long.MinValue;
            w[7] = long.MinValue;
        }
        return w.Max();
    }
}