public static Question generate()
{
List <RandNode> opdNodes = new List <RandNode> ();
List <RandNode> oprNodes = new List <RandNode> ();
string questionStr = "";
RandNode rn = getOpd(GlobalSettings.largestNum);
opdNodes.Add(rn);
questionStr += rn.number.ToString();
for (int i = 0; i < GlobalSettings.numberOfOperators - 1; i++)
{
RandNode opr = getOps();
/** Deal with divide, we only want integer for dividen **/
RandNode opd;
if (opr.type == QTree.Type.Div)
{
opd = getValidDivisor(getPrevDiv(oprNodes, opdNodes, opdNodes.Count - 1));
}
else
{
opd = getOpd(GlobalSettings.largestNum);
}
//Add them in
opdNodes.Add(opd);
oprNodes.Add(opr);
questionStr += " " + QTree.getOperatorStr(opr.type) + " " + opd.number.ToString();
}
//Debug.Log (questionStr);
QTree root = QTreeBuilder.build(opdNodes, oprNodes);
int rightAnswer = (int)root.evaluate();
int score = getScore(root);
string explaination = getExplaination(root);
Debug.Log("Explaination " + explaination + ", " + score);
Question question = new Question(questionStr, rightAnswer, score, explaination);
//Debug.Log ("The correct answer is " + question.answer.ToString ());
return(question);
}
/*
* 5 + 6 * 3 / 2 - 3
* =5 + 18 / 2 - 3
* =5 + 9 -3
* =14 - 3
* =11
* BFS to a stack, then pop out
*
*/
private static string getExplaination(QTree root)
{
Stack <string> exp = new Stack <string> ();
//bfs
Stack <QTreeExt> nodes = new Stack <QTreeExt>();
nodes.Push(new QTreeExt(root, false));
while (nodes.Count > 0)
{
Stack <QTreeExt> nextLevel = new Stack <QTreeExt> ();
string levelRes = "";
while (nodes.Count > 0)
{
QTreeExt qt = nodes.Pop();
if (qt.isVisited)
{
levelRes += QTree.getOperatorStr(qt.type);
}
else
{
levelRes += qt.evaluate();
if (qt.left != null && qt.right != null)
{
nextLevel.Push(new QTreeExt(qt.left, false));
nextLevel.Push(new QTreeExt(qt, true)); //make sure we don't visit this again
nextLevel.Push(new QTreeExt(qt.right, false));
}
}
}
nodes = nextLevel;
exp.Push(levelRes);
}
//pop the result stack
string result = " ";
while (exp.Count > 0)
{
result += exp.Pop();
result += "\n=";
}
return(result);
}