private void addNode(int num, IntegerTreeNode node) {
if (node.getValue() > num) {
if (node.getLeft() == null) {
node.setLeft(new IntegerTreeNode(num));
} else {
addNode(num, node.getLeft());
}
} else {
if (node.getRight() == null) {
node.setRight(new IntegerTreeNode(num));
} else {
addNode(num, node.getRight());
}
}
}
private IntegerTreeNode rotate(IntegerTreeNode tree) {
if (tree == null) {
return null;
}
IntegerTreeNode head = tree;
if (treeDepth(tree.getLeft()) > treeDepth(tree.getRight())) {
tree = tree.getLeft();
head.setLeft(tree.getRight());
tree.setRight(head);
} else {
tree = tree.getRight();
head.setRight(tree.getLeft());
tree.setLeft(head);
}
return tree;
}
private boolean unbalanced(IntegerTreeNode node) {
if (node == null) {
return false;
}
int left = treeDepth(node.getLeft());
int right = treeDepth(node.getRight());
return (Math.abs(left - right) > 1);
}
private int treeDepth(IntegerTreeNode node) {
if (node == null) {
return 0;
}
int left = treeDepth(node.getLeft());
int right = treeDepth(node.getRight());
return left > right ? left + 1 : right + 1;
}
private String toString(StringBuilder builder, IntegerTreeNode tree) {
if (tree == null) {
return builder.toString();
}
builder.append(toString(builder, tree.getLeft()));
builder.append(toString(builder, tree.getRight()));
return tree.toString();
}
private IntegerTreeNode rebalance(IntegerTreeNode tree) {
if (tree == null) {
return null;
}
tree.setLeft(rebalance(tree.getLeft()));
tree.setRight(rebalance(tree.getRight()));
if (unbalanced(tree)) {
tree = rotate(tree);
}
return tree;
}
private boolean contains(int num, IntegerTreeNode tree) {
if (tree == null) {
return false;
}
if (tree.getValue() == num) {
return true;
}
if (tree.getValue() < num) {
return contains(num, tree.getRight());
} else {
return contains(num, tree.getLeft());
}
}
private boolean containsVerbose(int num, IntegerTreeNode tree) {
System.out.println(tree);
if (tree == null) {
return false;
}
if (tree.getValue() == num) {
return true;
}
if (tree.getValue() < num) {
return contains(num, tree.getRight());
} else {
return contains(num, tree.getLeft());
}
}
