C#

private static string Format(string text) 
{
	System.Text.StringBuilder b = new System.Text.StringBuilder();
	int counter = 0;
	for (int i = 0; i < text.Length; i++) 
	{
		b.Append(text[i]);
		if (char.IsNumber(text[i])) 
		{
			counter++;
			if (counter == 6) 
			{
				b.Append(' ');
				counter = 0;
			}
		}
	}
	return b.ToString();
}

using System;
using System.ComponentModel;
using System.Drawing;
using System.Runtime.InteropServices;
 
class Click
{
  static void Main(string[] args)
  {
    if (args.Length != 2)
      Environment.Exit(1);
 
    Point p = new Point();
    p.X = int.Parse(args[0]);
    p.Y = int.Parse(args[1]);
 
    ClickAt(p);
  }
 
  [DllImport("user32.dll", SetLastError=true)]
  [return: MarshalAs(UnmanagedType.U4)]
  static extern int SendInput(
    [MarshalAs(UnmanagedType.U4)] int nInputs,
    INPUT[] pInputs,
    int cbSize);
 
  [StructLayout(LayoutKind.Explicit)]
  struct INPUT
  {
    [FieldOffset(0), MarshalAs(UnmanagedType.U4)] public int type;
    [FieldOffset(4)] public MOUSEINPUT mi;
    // [FieldOffset(4)] public KEYBDINPUT ki;
    // [FieldOffset(4)] public HARDWAREINPUT hi;
  }
 
  const int INPUT_MOUSE = 0;
  const int INPUT_KEYBOARD = 1;
  const int INPUT_HARDWARE = 2;
 
  [StructLayout(LayoutKind.Sequential)]
  struct MOUSEINPUT
  {
    public int dx;
    public int dy;
    [MarshalAs(UnmanagedType.U4)] public int mouseData;
    [MarshalAs(UnmanagedType.U4)] public int dwFlags;
    [MarshalAs(UnmanagedType.U4)] public int time;
    [MarshalAs(UnmanagedType.SysUInt)] public IntPtr dwExtraInfo;
  }
 
  const int MOUSEEVENTF_ABSOLUTE = 0x8000;
 
  public static void ClickAt(Point p)
  {
    MOUSEINPUT mi = new MOUSEINPUT();
    mi.dx = p.X;
    mi.dy = p.Y;
    mi.dwFlags = MOUSEEVENTF_ABSOLUTE;
 
    INPUT[] inputs = new INPUT[1];
    inputs[0].type = INPUT_MOUSE;
    inputs[0].mi = mi;
 
    int ret = SendInput(1, inputs, Marshal.SizeOf(typeof(INPUT)));
    if (ret != 0)
      throw new Win32Exception();
  }
}