输出数组中第二大数

class Program
{
private static int get2rdMax(int[] ar)
{
int max = ar[1], s_max = ar[1];
for (int i = 0; i < ar.Length; i++)
{
if (ar[i] > s_max)
{
s_max = ar[i];
if (s_max > max)
{
max += s_max;
s_max = max - s_max;
max -= s_max;
}
}
}

if (max == s_max)
throw new Exception("no second max!");
else
return s_max;
}

static void Main(string[] args)
{
int[] ar = { 1, 2, 3, 4, 5, 6 };
try
{
Console.WriteLine(get2rdMax(ar).ToString());
}
catch (Exception exc)
{
Console.WriteLine(exc.Message);
}
Console.ReadKey();

}
}