diff --git a/command/remote/app.d b/command/remote/app.d
index 5133a5d..4b2632f 100644
--- a/command/remote/app.d
+++ b/command/remote/app.d
@@ -39,7 +39,7 @@ void main()
     remoteControl.setCommand(0, livingRoomLightOn, livingRoomLightOff);
     remoteControl.setCommand(1, kitchenLightOn, kitchenLightOff);
     remoteControl.setCommand(2, ceilingFanOn, ceilingFanOff);
-    remoteControl.setCommand(2, stereoOnWithCD, stereoOff);
+    remoteControl.setCommand(3, stereoOnWithCD, stereoOff);
     remoteControl.setCommand(4, garageDoorUp, garageDoorDown);
 
     writeln(remoteControl);
diff --git a/command/remote/remotecontrol.d b/command/remote/remotecontrol.d
index 797965e..b842b2c 100644
--- a/command/remote/remotecontrol.d
+++ b/command/remote/remotecontrol.d
@@ -5,6 +5,8 @@ import command.remote.nocommand;
 import std.conv : to;
 import std.stdio : writeln;
 import std.algorithm.mutation : fill;
+import std.array : split, back;
+import std.format;
 
 class RemoteControl
 {
@@ -41,8 +43,10 @@ class RemoteControl
         string s = "\n------ Remote Control -------\n";
         for (int i = 0; i < 7; ++i)
         {
-            s ~= "[slot " ~ i.to!string ~ "] " ~ typeof(onCommands[i]).stringof
-                                        ~ "    " ~ typeof(offCommands[i]).stringof ~ "\n";
+            s ~= "[slot " ~ i.to!string ~ "] "
+                ~ format("%22s", (cast(Object)onCommands[i]).classinfo.name.split(".").back())
+                ~ format("%23s", (cast(Object)offCommands[i]).classinfo.name.split(".").back())
+                ~ "\n";
         }
 
         return s;
diff --git a/command/remoteundo/app.d b/command/remoteundo/app.d
new file mode 100644
index 0000000..fed0b16
--- /dev/null
+++ b/command/remoteundo/app.d
@@ -0,0 +1,52 @@
+module command.remoteundo.app;
+
+import command.remoteundo.remotecontrol;
+import command.remoteundo.lightoncommand;
+import command.remoteundo.lightoffcommand;
+import command.remoteundo.light;
+import command.remoteundo.ceilingfan;
+import command.remoteundo.ceilingfanoffcommand;
+import command.remoteundo.ceilingfanoncommand;
+import command.remoteundo.garagedoorupcommand;
+import command.remoteundo.garagedoordowncommand;
+import command.remoteundo.garagedoor;
+import command.remoteundo.stereoonwithcdcommand;
+import command.remoteundo.stereo;
+import command.remoteundo.stereooffcommand;
+import std.stdio : writeln;
+
+void main()
+{
+    auto remoteControl = new RemoteControl();
+
+    auto livingRoomLight = new Light("Living Room");
+    // auto kitchenLight =  new Light("Kitchen");
+    // auto ceilingFan = new CeilingFan("Living Room");
+    // auto garageDoor = new GarageDoor("Garage");
+    // auto stereo = new Stereo("Living Room");
+
+    remoteControl.setCommand(0, new LightOnCommand(livingRoomLight), new LightOffCommand(livingRoomLight));
+    // remoteControl.setCommand(1, new LightOnCommand(kitchenLight), new LightOffCommand(kitchenLight));
+    // remoteControl.setCommand(2, new CeilingFanOnCommand(ceilingFan), new CeilingFanOffCommand(ceilingFan));
+    // remoteControl.setCommand(3, new StereoOnWithCDCommand(stereo), new StereoOffCommand(stereo));
+    // remoteControl.setCommand(4, new GarageDoorUpCommand(garageDoor), new GarageDoorDownCommand(garageDoor));
+
+    // writeln(remoteControl);
+
+    remoteControl.onButtonWasPushed(0);
+    remoteControl.offButtonWasPushed(0);
+    writeln(remoteControl);
+    remoteControl.undoButtonWasPushed();
+    remoteControl.offButtonWasPushed(0);
+    remoteControl.onButtonWasPushed(0);
+    writeln(remoteControl);
+    remoteControl.undoButtonWasPushed();
+    // remoteControl.onButtonWasPushed(1);
+    // remoteControl.offButtonWasPushed(1);
+    // remoteControl.onButtonWasPushed(2);
+    // remoteControl.offButtonWasPushed(2);
+    // remoteControl.onButtonWasPushed(3);
+    // remoteControl.offButtonWasPushed(3);
+    // remoteControl.onButtonWasPushed(4);
+    // remoteControl.offButtonWasPushed(4);
+}
diff --git a/command/remoteundo/ceilingfan.d b/command/remoteundo/ceilingfan.d
new file mode 100644
index 0000000..99c5607
--- /dev/null
+++ b/command/remoteundo/ceilingfan.d
@@ -0,0 +1,48 @@
+module command.remoteundo.ceilingfan;
+
+import std.stdio : writeln;
+
+class CeilingFan
+{
+    private string location;
+    private int level;
+
+    static int HIGH = 2;
+    static int MEDIUM = 1;
+    static int LOW = 0;
+
+    this(string location)
+    {
+        this.location = location;
+    }
+    
+    void high()
+    {
+        level = HIGH;
+        writeln(location ~ " ceiling fan is on high");
+ 
+    } 
+
+    void medium()
+    {
+        level = MEDIUM;
+        writeln(location ~ " ceiling fan is on medium");
+    }
+
+    void low()
+    {
+        level = LOW;
+        writeln(location ~ " ceiling fan is on low");
+    }
+ 
+    void off()
+    {
+        level = 0;
+        writeln(location ~ " ceiling fan is off");
+    }
+ 
+    int getSpeed()
+    {
+        return level;
+    }
+}
diff --git a/command/remoteundo/ceilingfanoffcommand.d b/command/remoteundo/ceilingfanoffcommand.d
new file mode 100644
index 0000000..dad5174
--- /dev/null
+++ b/command/remoteundo/ceilingfanoffcommand.d
@@ -0,0 +1,24 @@
+module command.remoteundo.ceilingfanoffcommand;
+
+import command.remoteundo.command;
+import command.remoteundo.ceilingfan;
+
+class CeilingFanOffCommand : Command
+{
+    CeilingFan ceilingFan;
+
+    this(CeilingFan ceilingFan)
+    {
+        this.ceilingFan = ceilingFan;
+    }
+
+    void execute()
+    {
+        ceilingFan.off();
+    }
+
+    void undo()
+    {
+        ceilingFan.high();
+    }
+}
diff --git a/command/remoteundo/ceilingfanoncommand.d b/command/remoteundo/ceilingfanoncommand.d
new file mode 100644
index 0000000..8f2b683
--- /dev/null
+++ b/command/remoteundo/ceilingfanoncommand.d
@@ -0,0 +1,24 @@
+module command.remoteundo.ceilingfanoncommand;
+
+import command.remoteundo.command;
+import command.remoteundo.ceilingfan;
+
+class CeilingFanOnCommand : Command
+{
+    CeilingFan ceilingFan;
+
+    this(CeilingFan ceilingFan)
+    {
+        this.ceilingFan = ceilingFan;
+    }
+
+    void execute()
+    {
+        ceilingFan.high();
+    }
+
+    void undo()
+    {
+        ceilingFan.off();
+    }
+}
diff --git a/command/remoteundo/command.d b/command/remoteundo/command.d
new file mode 100644
index 0000000..fe1bba1
--- /dev/null
+++ b/command/remoteundo/command.d
@@ -0,0 +1,7 @@
+module command.remoteundo.command;
+
+interface Command
+{
+    void execute();
+    void undo();
+}
diff --git a/command/remoteundo/garagedoor.d b/command/remoteundo/garagedoor.d
new file mode 100644
index 0000000..720f224
--- /dev/null
+++ b/command/remoteundo/garagedoor.d
@@ -0,0 +1,38 @@
+module command.remoteundo.garagedoor;
+
+import std.stdio : writeln;
+
+class GarageDoor
+{
+    private string location;
+
+    this(string location)
+    {
+        this.location = location;
+    }
+
+    void up()
+    {
+        writeln(location ~ " garage Door is Up");
+    }
+
+    void down()
+    {
+        writeln(location ~ " garage Door is Down");
+    }
+
+    void stop()
+    {
+        writeln(location ~ " garage Door is Stopped");
+    }
+
+    void lightOn()
+    {
+        writeln(location ~ " garage light is on");
+    }
+
+    void lightOff()
+    {
+        writeln(location ~ " garage light is off");
+    }
+}
diff --git a/command/remoteundo/garagedoordowncommand.d b/command/remoteundo/garagedoordowncommand.d
new file mode 100644
index 0000000..d9d3c24
--- /dev/null
+++ b/command/remoteundo/garagedoordowncommand.d
@@ -0,0 +1,24 @@
+module command.remoteundo.garagedoordowncommand;
+
+import command.remoteundo.command;
+import command.remoteundo.garagedoor;
+
+class GarageDoorDownCommand : Command
+{
+    GarageDoor garageDoor;
+
+    this(GarageDoor garageDoor)
+    {
+        this.garageDoor = garageDoor;
+    }
+
+    void execute()
+    {
+        garageDoor.down();
+    }
+
+    void undo()
+    {
+        garageDoor.up();
+    }
+}
diff --git a/command/remoteundo/garagedoorupcommand.d b/command/remoteundo/garagedoorupcommand.d
new file mode 100644
index 0000000..70cdb0d
--- /dev/null
+++ b/command/remoteundo/garagedoorupcommand.d
@@ -0,0 +1,24 @@
+module command.remoteundo.garagedoorupcommand;
+
+import command.remoteundo.command;
+import command.remoteundo.garagedoor;
+
+class GarageDoorUpCommand : Command
+{
+    GarageDoor garageDoor;
+
+    this(GarageDoor garageDoor)
+    {
+        this.garageDoor = garageDoor;
+    }
+
+    void execute()
+    {
+        garageDoor.up();
+    }
+
+    void undo()
+    {
+        garageDoor.down();
+    }
+}
diff --git a/command/remoteundo/light.d b/command/remoteundo/light.d
new file mode 100644
index 0000000..ad6f09b
--- /dev/null
+++ b/command/remoteundo/light.d
@@ -0,0 +1,23 @@
+module command.remoteundo.light;
+
+import std.stdio : writeln;
+
+class Light
+{
+    private string location;
+
+    this(string location)
+    {
+        this.location = location;
+    }
+
+    void on()
+    {
+        writeln(location ~ " light is On");
+    }
+
+    void off()
+    {
+        writeln(location ~ " light is Off");
+    }
+}
diff --git a/command/remoteundo/lightoffcommand.d b/command/remoteundo/lightoffcommand.d
new file mode 100644
index 0000000..638a7e8
--- /dev/null
+++ b/command/remoteundo/lightoffcommand.d
@@ -0,0 +1,24 @@
+module command.remoteundo.lightoffcommand;
+
+import command.remoteundo.command;
+import command.remoteundo.light;
+
+class LightOffCommand : Command
+{
+    Light light;
+
+    this(Light light)
+    {
+        this.light = light;
+    }
+
+    void execute()
+    {
+        light.off();
+    }
+
+    void undo()
+    {
+        light.on();
+    }
+}
diff --git a/command/remoteundo/lightoncommand.d b/command/remoteundo/lightoncommand.d
new file mode 100644
index 0000000..1a94203
--- /dev/null
+++ b/command/remoteundo/lightoncommand.d
@@ -0,0 +1,24 @@
+module command.remoteundo.lightoncommand;
+
+import command.remoteundo.command;
+import command.remoteundo.light;
+
+class LightOnCommand : Command
+{
+    Light light;
+
+    this(Light light)
+    {
+        this.light = light;
+    }
+
+    void execute()
+    {
+        light.on();
+    }
+
+    void undo()
+    {
+        light.off();
+    }
+}
diff --git a/command/remoteundo/nocommand.d b/command/remoteundo/nocommand.d
new file mode 100644
index 0000000..e81c3fd
--- /dev/null
+++ b/command/remoteundo/nocommand.d
@@ -0,0 +1,9 @@
+module command.remoteundo.nocommand;
+
+import command.remoteundo.command;
+
+class NoCommand : Command
+{
+    void execute() {}
+    void undo() {}
+}
diff --git a/command/remoteundo/remotecontrol.d b/command/remoteundo/remotecontrol.d
new file mode 100644
index 0000000..7cba07a
--- /dev/null
+++ b/command/remoteundo/remotecontrol.d
@@ -0,0 +1,63 @@
+module command.remoteundo.remotecontrol;
+
+import command.remoteundo.command;
+import command.remoteundo.nocommand;
+import std.conv : to;
+import std.stdio : writeln;
+import std.algorithm.mutation : fill;
+import std.array : split, back;
+import std.format;
+
+class RemoteControl
+{
+    Command[] onCommands;
+    Command[] offCommands;
+    Command undoCommand;
+
+    this()
+    {
+        onCommands = new Command[7];
+        offCommands = new Command[7];
+        Command noCommand = new NoCommand();
+        fill(onCommands, noCommand);        
+        fill(offCommands, noCommand);
+        undoCommand = noCommand;
+    }
+
+    void setCommand(int slot, Command onCommand, Command offCommand)
+    {
+        onCommands[slot] = onCommand;
+        offCommands[slot] = offCommand;
+    }
+
+    void onButtonWasPushed(int slot)
+    {
+        onCommands[slot].execute();
+        undoCommand = onCommands[slot];
+    }
+
+    void offButtonWasPushed(int slot)
+    {
+        offCommands[slot].execute();
+        undoCommand = offCommands[slot];
+    }
+
+    void undoButtonWasPushed()
+    {
+        undoCommand.undo();
+    }
+
+    override string toString() const
+    {
+        string s = "\n------ Remote Control -------\n";
+        for (int i = 0; i < 7; ++i)
+        {
+            s ~= "[slot " ~ i.to!string ~ "] "
+                ~ format("%22s", (cast(Object)onCommands[i]).classinfo.name.split(".").back())
+                ~ format("%23s", (cast(Object)offCommands[i]).classinfo.name.split(".").back())
+                ~ "\n";
+        }
+
+        return s ~ "[undo] " ~ (cast(Object)undoCommand).classinfo.name.split(".").back() ~ "\n";
+    }
+}
diff --git a/command/remoteundo/stereo.d b/command/remoteundo/stereo.d
new file mode 100644
index 0000000..167efb9
--- /dev/null
+++ b/command/remoteundo/stereo.d
@@ -0,0 +1,44 @@
+module command.remoteundo.stereo;
+
+import std.stdio : writeln;
+import std.conv : to;
+
+class Stereo
+{
+    string location;
+
+    this(string location)
+    {
+        this.location = location;
+    }
+
+    void on()
+    {
+        writeln(location ~ " stereo is on");
+    }
+
+    void off()
+    {
+        writeln(location ~ " stereo is off");
+    }
+
+    void setCD()
+    {
+        writeln(location ~ " stereo is set for CD input");
+    }
+
+    void setDVD()
+    {
+        writeln(location ~ " stereo is set for DVD input");
+    }
+
+    void setRadio()
+    {
+        writeln(location ~ " stereo is set for Radio");
+    }
+
+    void setVolume(int volume)
+    {
+        writeln(location ~ " stereo volume set to " ~ volume.to!string);
+    }
+}
diff --git a/command/remoteundo/stereooffcommand.d b/command/remoteundo/stereooffcommand.d
new file mode 100644
index 0000000..5f79e61
--- /dev/null
+++ b/command/remoteundo/stereooffcommand.d
@@ -0,0 +1,26 @@
+module command.remoteundo.stereooffcommand;
+
+import command.remoteundo.command;
+import command.remoteundo.stereo;
+
+class StereoOffCommand : Command
+{
+    Stereo stereo;
+ 
+    this(Stereo stereo)
+    {
+        this.stereo = stereo;
+    }
+ 
+    void execute()
+    {
+        stereo.off();
+    }
+
+    void undo()
+    {
+        stereo.on();
+        stereo.setCD();
+        stereo.setVolume(11);
+    }
+}
diff --git a/command/remoteundo/stereoonwithcdcommand.d b/command/remoteundo/stereoonwithcdcommand.d
new file mode 100644
index 0000000..222899c
--- /dev/null
+++ b/command/remoteundo/stereoonwithcdcommand.d
@@ -0,0 +1,26 @@
+module command.remoteundo.stereoonwithcdcommand;
+
+import command.remoteundo.command;
+import command.remoteundo.stereo;
+
+class StereoOnWithCDCommand : Command
+{
+    Stereo stereo;
+ 
+    this(Stereo stereo)
+    {
+        this.stereo = stereo;
+    }
+ 
+    void execute()
+    {
+        stereo.on();
+        stereo.setCD();
+        stereo.setVolume(11);
+    }
+
+    void undo()
+    {
+        stereo.off();
+    }
+}