// Constructor
public AStar(World w, aNode start, aNode goal)
{
openList = new OpenList<aNode>();
closedList = new ArrayList();
startNode = start;
goalNode = goal;
thisWorld = w;
}
public static void Main(string[] args)
{
World world = new World ();
bool dataValid;
int[] matchesArray = new int[2];
int userBeginX, userBeginY, userGoalX, userGoalY;
char newIOPos, newWorld;
bool firstRun = true;
do {
world.generateUnpathableBlocks ();
do {
Console.Clear();
if (firstRun) {
Console.Write(world.worldPrint () + "\n");
Console.WriteLine("Welcome! This is a demo of the A* pathfinding algorithm.");
Console.WriteLine("(Grid Positions can be entered as (1,1) or 1,1 or 1 1.)\n");
} else
Console.Write(world.worldPrint() + "\n\n\n");
MatchCollection matches = null;
do { // for data validation
Console.Write ("Enter (x,y) for the start position: ");
dataValid = false;
String temp = Console.ReadLine ();
matches = Regex.Matches (temp, @"\d+");
if (matches.Count == 2) {
dataValid = true;
int val = 0;
for (int i = 0; i < 2 && dataValid; i++) {
matchesArray[i] =
((Int32.TryParse(matches[i].Value, out val)) &&
val <= 15 && val > 0) ? val : -1;
dataValid = matchesArray[i] == -1 ? false: true;
}
}
dataValid = world.blockIsPathable(matchesArray[0] - 1, matchesArray[1] - 1);
if (!dataValid)
Console.WriteLine("The coordinates you entered were not accepted.");
} while (!dataValid);
userBeginX = matchesArray[0];
userBeginY = matchesArray[1];
matchesArray [0] = matchesArray [1] = 0;
// goal entry
do { // for data validation
Console.Write ("Enter (x,y) for the goal position: ");
dataValid = false;
String temp = Console.ReadLine ();
matches = Regex.Matches (temp, @"\d+");
if (matches.Count == 2) {
dataValid = true;
int val = 0;
for (int i = 0; i < 2 && dataValid; i++) {
matchesArray[i] =
((Int32.TryParse(matches[i].Value, out val)) &&
val <= 15 && val > 0) ? val : -1;
dataValid = matchesArray[i] == -1 ? false: true;
}
}
dataValid = world.blockIsPathable(matchesArray[0] - 1, matchesArray[1] - 1) && dataValid;
if (!dataValid)
Console.WriteLine("The coordinates you entered were not accepted.");
} while (!dataValid);
userGoalX = matchesArray [0];
userGoalY = matchesArray [1];
// initialize the start node and goal node
aNode beginNode = new aNode (userBeginX-1, userBeginY-1);
aNode goalNode = new aNode (userGoalX-1, userGoalY-1);
// find the solution
AStar aStarInstance = new AStar (world, beginNode, goalNode);
bool solutionExists = aStarInstance.AStarSearch ();
if (solutionExists && aStarInstance.generatedPath.Count > 1) { // print solution
Console.Clear();
Console.Write(world.worldPrint(aStarInstance.generatedPath, beginNode, goalNode));
Console.WriteLine("\nThe path was found!");
Console.WriteLine("Here is the path from start to finish:");
foreach (aNode n in aStarInstance.generatedPath)
Console.Write("({0},{1}) ", n.x+1, n.y+1);
Console.Write("\n");
} else if (solutionExists && aStarInstance.generatedPath.Count == 1) {
Console.Clear();
Console.Write(world.worldPrint(aStarInstance.generatedPath));
Console.WriteLine("\nLooks like you didn't go anywhere...");
Console.WriteLine("Here is where you started and ended:");
foreach (aNode n in aStarInstance.generatedPath)
Console.Write("({0},{1}) ", n.x+1, n.y+1);
Console.Write("\n");
} else {
Console.Clear();
Console.Write("\n\n" + world.worldPrint(beginNode, goalNode));
Console.WriteLine("\nNo path found.\n");
Console.Write("\n");
}
// same board, new positions?
Console.Write("\n Would you like to try new start and goal positions? : [YyNn] ");
do {
try {
newIOPos = Console.ReadLine()[0];
} catch {
dataValid = false;
newIOPos = 'f';
continue;
}
if (newIOPos != 'Y' && newIOPos != 'y' && newIOPos != 'N' && newIOPos != 'n')
{
dataValid = false;
Console.Write("Key invalid. (Try Y or N)");
}
else
{
dataValid = true;
if(newIOPos == 'y' || newIOPos == 'Y') {
Console.Clear();
Console.Write("\n\n\n");
}
}
} while (!dataValid);
} while (newIOPos == 'y' || newIOPos == 'Y');
// new board and positions?
Console.Write(" Would you like to try with a new board? : [YyNn] ");
do {
try {
newWorld = Console.ReadLine()[0];
} catch {
dataValid = false;
newWorld = 'f';
continue;
}
if (newWorld != 'Y' && newWorld != 'y' && newWorld != 'N' && newWorld != 'n')
{
dataValid = false;
Console.Write("Key invalid. (Try Y or N)");
}
else
{
dataValid = true;
}
} while (!dataValid);
} while (newWorld == 'y' || newWorld == 'Y');
Console.WriteLine ("Thanks for the visit. \nPress any key...");
Console.Read ();
}
