@@ -8,8 +8,9 @@
 	public immutable int y, x;
 	mixin DeriveCreate;
 	mixin DeriveCompare;
 	mixin DeriveShow;
+	Pos clone() { return this; }
 
 @property:
 	Pos wait()  { return this; }
 	Pos up()    { return new Pos(y+1, x); }
@@ -44,8 +45,9 @@
 	public immutable int base, pace;
 	mixin DeriveCreate;
 	mixin DeriveCompare;
 	mixin DeriveShow;
+	Water clone() { return this; }
 
 	static load(string[string] params)
 	{
 		return new Water(
@@ -101,8 +103,16 @@
 		char[][] data;
 		Pos robot;
 		Pos lift;
 		int waterproof;
+	}
+	Map clone() { return new Map(this); }
+	this(Map m) {
+		foreach(s; m.data)
+			this.data ~= s.dup;
+		this.robot = m.robot.clone();
+		this.lift = m.lift.clone();
+		this.waterproof = m.waterproof;
 	}
 
 	this(string[] raw_data, string[string] params)
 	{
@@ -285,15 +295,31 @@
 		this.map = Map.load(raw_data, params);
 		this.water = Water.load(params);
 		this.output = new NilOutput;
 	}
+
+	Game clone() { return new Game(this); }
+	this(Game g) {
+		map = g.map.clone();
+		water = g.water.clone();
+		output = new NilOutput;
+		turn = g.turn;
+		dead = g.dead;
+		lambda = g.lambda;
+		exit_bonus = g.exit_bonus;
+		under_water = g.under_water;
+	}
 
 	void set_output(Output o) { this.output = (o is null ? new NilOutput : o); }
 
 	void command(char c)
 	{
 		if(dead || cleared)
 			return;
+		scope(exit) {
+			if(dead || cleared)
+				output.flush();
+		}
 		this.output.command(c);
 
 		if(c == 'A')
 		{
@@ -312,31 +338,33 @@
 				dead = true;
 			}
 		}
 		if( map.robot.y <= water_level )
-			++under_warter;
+			++under_water;
 		else
-			under_warter = 0;
-		if( under_warter > map.waterproof )
+			under_water = 0;
+		if( under_water > map.waterproof )
 			dead = true;
 		turn += 1;
 	}
 
 	Map map;
 	Water water;
 	Output output;
-
 	int  turn = 0;
 	bool dead = false;
 	int  lambda = 0;
 	int  exit_bonus = 0;
-	int  under_warter = 0;
+	int  under_water = 0;
+	// TODO: when adding members, take care of clone().
+	// TODO: fix this poor design.
+
 	@property {
 		long score() { return lambda*25L*(1+exit_bonus) - turn; }
 		int water_level() { return water.level(turn); }
 		int water_until_rise() { return water.until_rise(turn); }
 		bool cleared() { return exit_bonus>0; }
-		int hp() { return map.waterproof - under_warter; }
+		int hp() { return map.waterproof - under_water; }
 		long score_if_abort_now() { return lambda*25*(1+max(1,exit_bonus)) - turn; }
 	}
 }