public Solution(Puzzle puzzle, State final, HashSet<State> reachedStates, HashSet<State> statesExitReachedFrom = null)
{
this.puzzle = puzzle;
this.final = final;
this.reachedStates = reachedStates;
this.statesExitReachedFrom = statesExitReachedFrom ?? new HashSet<State>();
}
public void Move(string locationName, string liftName = null)
{
Edge edge = state.position.edgesFrom.FirstOrDefault(e => e.to.name == locationName && e.Move(state) != null && (liftName == null || e.lift != null && e.lift.name == liftName));
if (edge == null) {
throw new Exception(String.Format("Move to {0}{1} failed: no suitable edge", locationName, liftName != null ? string.Format(" via {0)", liftName) : ""));
}
state = edge.Move(state);
}
public State Unpush(State state)
{
if (state.calledLifts.Count == 0 || state.calledLifts.Last() != this.target) {
return null;
}
var result = state.Clone();
result.calledLifts.RemoveAt(result.calledLifts.Count - 1);
result.SetNext(state, new Push(this));
return result;
}
public State Push(State state)
{
if (state.calledLifts.Contains(target)) {
return null;
}
var result = state.Clone();
result.calledLifts.Add(target);
result.SetPrevious(state, new Push(this));
return result;
}
static void TestComparer()
{
Puzzle puzzle = Puzzles.Raise();
State state1 = new State(puzzle.start, new List<Lift>() { puzzle.locations[0].edgesFrom[0].lift });
State state2 = new State(puzzle.start, new List<Lift>() { puzzle.locations[0].edgesFrom[0].lift });
StateComparer comparer = new StateComparer();
Console.WriteLine(comparer.Equals(state1, state2));
Console.WriteLine(comparer.GetHashCode(state1));
Console.WriteLine(comparer.GetHashCode(state2));
Console.ReadLine();
}
public void Call(string liftName)
{
var button = state.position.buttons.FirstOrDefault(b => b.target.name == liftName);
if (button == null) {
throw new Exception(String.Format("Call {0} failed: no button for such lift at current position {1}", liftName, state.position));
}
if (state.calledLifts.Contains(button.target)) {
throw new Exception(String.Format("Call {0} failed: already in queue", liftName));
}
state = button.Push(state);
}
public State Unmove(State state)
{
if (this.lift != null && (state.calledLifts.Contains(this.lift))) {
return null;
}
var result = state.Clone();
result.position = from;
if (this.lift != null) {
result.calledLifts.Insert(0, this.lift);
}
result.SetNext(state, new Move(this));
return result;
}
public State Move(State state)
{
if (this.lift != null && (state.calledLifts.Count == 0 || state.calledLifts[0] != this.lift)) {
return null;
}
var result = state.Clone();
result.position = to;
if (this.lift != null) {
result.calledLifts.RemoveAt(0);
}
result.SetPrevious(state, new Move(this));
return result;
}
public static void Bfs(Puzzle puzzle, HashSet<State> reachedStates, State start)
{
Queue<State> queue = new Queue<State>();
queue.Enqueue(start);
reachedStates.Add(start);
while (queue.Count > 0) {
List<State> nextStates = NextStates(puzzle, queue.Dequeue());
nextStates.ForEach(nextState => {
if (!reachedStates.Contains(nextState)) {
reachedStates.Add(nextState);
queue.Enqueue(nextState);
}
});
}
}
public static List<State> PreviousStates(Puzzle puzzle, State state)
{
var result = new List<State>();
state.position.edgesTo.ForEach(edge => {
var prevState = edge.Unmove(state);
if (prevState != null) {
result.Add(prevState);
}
});
state.position.buttons.ForEach(button => {
var prevState = button.Unpush(state);
if (prevState != null) {
result.Add(prevState);
}
});
return result;
}
public static List<State> NextStates(Puzzle puzzle, State state)
{
var result = new List<State>();
state.position.edgesFrom.ForEach(edge => {
var nextState = edge.Move(state);
if (nextState != null) {
result.Add(nextState);
}
});
state.position.buttons.ForEach(button => {
var nextState = button.Push(state);
if (nextState != null) {
result.Add(nextState);
}
});
return result;
}
public void SetPrevious(State previous, Action actionFromPrevious)
{
this.previous = previous;
this.actionFromPrevious = actionFromPrevious;
}
public void SetNext(State next, Action actionToNext)
{
this.next = next;
this.actionToNext = actionToNext;
}
public static bool Final(State state)
{
return state.position.isExit;
}
public void Start()
{
state = new State(start);
}