public AStarSolve(int[] startList, int[] targetList)
{
if (startList.Length != 9 || targetList.Length != 9)
{
}
else
{
start = new StateNode(startList);
start.parent = -1; // no parent
string result = null;
for (int i = 0; i < 8; i++)
{
result += start.numbers[i].ToString() + ",";
}
result += start.numbers[8].ToString();
Console.WriteLine("Start node: " + result);
target = new StateNode(targetList);
listNode.Add(start);
int f = start.h;
H_front.Add(f);
frontier.Add(0); // the first node is on the frontier
start.g = 0;
}
}
public Boolean explore_Tree(int nodeIndexP)
{
StateNode start = new StateNode(listNode[nodeIndexP].numbers);
// ==== Printing numbers of this node ====
string result = null;
for (int i = 0; i < 8; i++)
{
result += listNode[nodeIndexP].numbers[i].ToString() + ",";
}
result += listNode[nodeIndexP].numbers[8].ToString();
// Console.WriteLine("Start explore for node: " + nodeIndexP.ToString() + " =: " + result);
// ========
// Using the position of number 0, choose the possible neighbers
int index = Array.IndexOf(start.numbers, 0);
int[] tryNumbers = new int[9];
int row = index / 3; // Row of number 0
int col = index % 3; // Col of number 0
StateNode tryNode;
int chosenNode = nodeIndexP;
int heuristic = 100;
int tryRow, tryCol;
tryRow = row - 1; tryCol = col;
{
if (tryRow > -1)
{
Array.Copy(start.numbers, tryNumbers, 9);
tryNumbers[index] = tryNumbers[3 * tryRow + tryCol];
tryNumbers[3 * tryRow + tryCol] = 0;
tryNode = new StateNode(tryNumbers);
tryNode.parent = nodeIndexP;
tryNode.g = listNode[nodeIndexP].g + step;
int chsId = listNode.FindIndex(f => f.checkSum == tryNode.checkSum);
if ((chsId >= 0)) // in the closed set
{
if (listNode[chsId].isXpanded)
{
// in closed set so ignore
}
else if ((listNode[chsId].h + listNode[chsId].g) <= (tryNode.h + tryNode.g)) // in open set, but higher g cost
{
// in closed set, but with higher g cost
}
else
{
listNode[chsId].g = tryNode.g;
listNode[chsId].parent = tryNode.parent;
int idFind = frontier.FindIndex(p => p == chsId);
H_front[idFind] = tryNode.h + tryNode.g;
}
}
else
{
listNode.Add(tryNode);
chosenNode = listNode.Count - 1;
frontier.Add(listNode.Count - 1); // the new node is on the frontier
int a = tryNode.h + tryNode.g;
H_front.Add(a);
heuristic = tryNode.h + tryNode.g;
}
}
}
tryRow = row + 1; tryCol = col;
{
if (tryRow < 3)
{
Array.Copy(start.numbers, tryNumbers, 9);
tryNumbers[index] = tryNumbers[3 * tryRow + tryCol];
tryNumbers[3 * tryRow + tryCol] = 0;
tryNode = new StateNode(tryNumbers);
tryNode.parent = nodeIndexP;
tryNode.g = listNode[nodeIndexP].g + step;
int chsId = listNode.FindIndex(f => f.checkSum == tryNode.checkSum);
if ((chsId >= 0)) // in the closed set
{
if (listNode[chsId].isXpanded)
{
// in closed sed, so ignore
}
else if ((listNode[chsId].h + listNode[chsId].g) <= (tryNode.h + tryNode.g)) // in open set, but higher g cost
{
// in closed set, but with higher g cost
}
else
{
listNode[chsId].g = tryNode.g;
listNode[chsId].parent = tryNode.parent;
int idFind = frontier.FindIndex(p => p == chsId);
H_front[idFind] = tryNode.h + tryNode.g;
}
}
else
{
listNode.Add(tryNode);
chosenNode = listNode.Count - 1;
frontier.Add(listNode.Count - 1); // the new node is on the frontier
int a = tryNode.h + tryNode.g;
H_front.Add(a);
heuristic = tryNode.h + tryNode.g;
}
}
}
tryRow = row; tryCol = col - 1;
{
if (tryCol > -1)
{
Array.Copy(start.numbers, tryNumbers, 9);
tryNumbers[index] = tryNumbers[3 * tryRow + tryCol];
tryNumbers[3 * tryRow + tryCol] = 0;
tryNode = new StateNode(tryNumbers);
tryNode.g = listNode[nodeIndexP].g + step;
tryNode.parent = nodeIndexP;
int chsId = listNode.FindIndex(f => f.checkSum == tryNode.checkSum);
if ((chsId >= 0)) // in the closed set
{
if (listNode[chsId].isXpanded)
{
// in closed sed, so ignore
}
else if ((listNode[chsId].h + listNode[chsId].g) <= (tryNode.h + tryNode.g)) // in open set, but higher g cost
{
// in closed set, but with higher g cost
}
else
{
listNode[chsId].g = tryNode.g;
listNode[chsId].parent = tryNode.parent;
int idFind = frontier.FindIndex(p => p == chsId);
H_front[idFind] = tryNode.h + tryNode.g;
}
}
else
{
listNode.Add(tryNode);
chosenNode = listNode.Count - 1;
frontier.Add(listNode.Count - 1); // the new node is on the frontier
int a = tryNode.h + tryNode.g;
H_front.Add(a);
heuristic = tryNode.h + tryNode.g;
}
}
}
tryRow = row; tryCol = col + 1;
{
if (tryCol < 3)
{
Array.Copy(start.numbers, tryNumbers, 9);
tryNumbers[index] = tryNumbers[3 * tryRow + tryCol];
tryNumbers[3 * tryRow + tryCol] = 0;
tryNode = new StateNode(tryNumbers);
tryNode.parent = nodeIndexP;
tryNode.g = listNode[nodeIndexP].g + step;
int chsId = listNode.FindIndex(f => f.checkSum == tryNode.checkSum);
if ((chsId >= 0)) // in the closed set
{
if (listNode[chsId].isXpanded)
{
// in closed sed, so ignore
}
else if ((listNode[chsId].h + listNode[chsId].g) <= (tryNode.h + tryNode.g)) // in open set, but higher g cost
{
// in closed set, but with higher g cost
}
else
{
listNode[chsId].g = tryNode.g;
listNode[chsId].parent = tryNode.parent;
int idFind = frontier.FindIndex(p => p == chsId);
H_front[idFind] = tryNode.h + tryNode.g;
}
}
else
{
listNode.Add(tryNode);
chosenNode = listNode.Count - 1;
frontier.Add(listNode.Count - 1); // the new node is on the frontier
int a = tryNode.h + tryNode.g;
H_front.Add(a);
heuristic = tryNode.h + tryNode.g;
}
}
}
listNode[nodeIndexP].isXpanded = true;
int idxFind = frontier.FindIndex(p => p == nodeIndexP);
frontier.RemoveAt(idxFind);
H_front.RemoveAt(idxFind);
{
int Hmin = H_front.Min();
var minimumValueIndex = H_front.IndexOf(H_front.Min());
chosenNode = frontier[minimumValueIndex];
if (listNode[chosenNode].h == 0)
{
return(true);
}
else
{
if (listNode.Count > 3000)
{
return(false);
}
else
{
return(true && explore_Tree(chosenNode));
}
}
}
}