public static void insert(TreeNode tnode, int x, TreeNode p) {
if (tnode == null) {
tnode = new TreeNode();
tnode.value = x;
tnode.lchild = null;
tnode.rchild = null;
if (p.value > x) p.lchild = tnode;
else p.rchild = tnode;
tnode.parent = p;
return;
}
if (x < tnode.value) {
insert(tnode.lchild, x, tnode);
} else {
insert(tnode.rchild, x, tnode);
}
}
/**
* Private method created for inserting into the tree. Works recursively returns false if point
* already in tree Method for inserting a node into the tree. Works by traversing through the
* tree, branches off x value for even cuts, and y for odd cuts. Uses other value as a tie
* breaker. Also keeps track of height and size for constant return time on those function calls.
*/
private boolean insert(TreeNode t, TreeNode prev, TreeNode newNode, boolean cd, boolean left) {
if (t == null) { // Found where node should live
if (left) {
prev.left = newNode;
} else {
prev.right = newNode;
}
newNode.cd = cd;
newNode.parent = prev;
size++;
return true;
} else if (t.p.equals(newNode.p)) return false; // Found the point, don't insert it
// Recursive calls to left or right tree
else if (cd) {
if (newNode.p.x() < t.p.x()) insert(t.left, t, newNode, !cd, true);
else if (newNode.p.x() > t.p.x()) insert(t.right, t, newNode, !cd, false);
else { // Tie breaker
if (newNode.p.y() < t.p.y()) insert(t.left, t, newNode, !cd, true);
else insert(t.right, t, newNode, !cd, false);
}
} else {
if (newNode.p.y() < t.p.y()) insert(t.left, t, newNode, !cd, true);
else if (newNode.p.y() > t.p.y()) insert(t.right, t, newNode, !cd, false);
else { // Tie breaker
if (newNode.p.x() < t.p.x()) insert(t.left, t, newNode, !cd, true);
else insert(t.right, t, newNode, !cd, false);
}
}
updateMinMax(t, newNode);
t.height = maxHeight(t.left, t.right) + 1;
// Now check if tree became unbalanced
if (unbalanced(t)) {
// System.out.println("unbalanced");
Point[] points = collectSatanSpawn(t);
TDTree newSubTree = new TDTree(points, cd);
swapDataMembers(t, newSubTree.root);
}
return true;
} // End private insert() method