public class BBST<Key extends Comparable<Key>, Value> {
private Node root;
public class Node {
private Key key;
private Value val;
private Node parent, left, right;
private int height;
private int bfc; //balance factor
private Node(Key key, Value val, int height, Node parent, int bfc) {
this.key = key;
this.val = val;
this.height = height;
this.parent = parent;
this.left = this.right = null;
this.bfc = bfc;
}
}
public Value Search(Key key) {
return SearchIn(root, key);
}
private Value SearchIn(Node t, Key key) {
if (t == null)
return null;
else if (key.compareTo(t.key) == 0)
return t.val;
return SearchIn(key.compareTo(t.key) < 0 ? t.left : t.right, key);
}
private void connect34(Node a, Node b, Node c, Node t0, Node t1, Node t2, Node t3) {
b.left = a;
b.right = c;
a.parent = b;
c.parent = b;
a.left = t0;
if (t0 != null)
t0.parent = a;
a.right = t1;
if (t1 != null)
t1.parent = a;
c.left = t2;
if (t2 != null)
t2.parent = c;
c.right = t3;
if (t3 != null)
t3.parent = c;
root = b;
}
private void UpdateHeight_BFC(Node x) {
Node x2 = x;
while (true) {
if (x.left == null && x.right == null) {
x.height = 0;
x.bfc = 0;
} else if (x.left == null)
x.height = x.right.height + 1;
else if (x.right == null) {
x.height = x.left.height + 1;
System.out.println(" ");
} else
x.height = (x.left.height == x.right.height ? x.left.height : x.left.height > x.right.height ? x.left.height : x.right.height) + 1;
if (x.parent == null)
break;
else
x = x.parent;
}
while (x2 != null) {
if (x2.left == null && x2.right == null) {
} else if (x2.left == null)
x2.bfc = 0 - x2.height;
else if (x2.right == null)
x2.bfc = x2.height;
else {
x2.bfc = x2.left.height - x2.right.height;
}
x2 = x2.parent;
}
root = x;
}
private boolean Balanced(Node t) {
return t.bfc < 2 && t.bfc > -2;
}
private void ReBalance(Node t) {
while (t != null) {
if (!Balanced(t)) {
Node son = null, grandson = null;
if (t.bfc > 1) { //左子树不平衡
son = t.left;
if (son.bfc < 0) { //左右
if (t.parent != null) {
if (t.parent.left != null && t.parent.left.key == t.key)
t.parent.left = son.right;
else
t.parent.right = son.right;
son.right.parent = t.parent;
}
son.right.parent = null;
connect34(son, son.right, t, son.left, son.right.left, son.right.right, t.right);
UpdateHeight_BFC(t);
UpdateHeight_BFC(son);
break;
} else { //左左
if (t.parent != null) {
if (t.parent.left != null && t.parent.left.key == t.key)
t.parent.left = son;
else
t.parent.right = son;
son.parent = t.parent;
}
son.parent = null;
connect34(son.left, son, t, son.left.left, son.left.right, son.right, t.right);
UpdateHeight_BFC(t);
UpdateHeight_BFC(son.left);
break;
}
} else { //右子树不平衡
son = t.right;
if (son.bfc < 0) { //右右
if (t.parent != null) {
if (t.parent.left != null && t.parent.left.key == t.key)
t.parent.left = son;
else
t.parent.right = son.left;
son.parent = t.parent;
}
son.parent = null;
connect34(t, son, son.right, t.left, son.left, son.right.left, son.right.right);
UpdateHeight_BFC(t);
UpdateHeight_BFC(son.right);
break;
} else { //右左
if (t.parent != null) {
if (t.parent.left != null && t.parent.left.key == t.key)
t.parent.left = son.left;
else
t.parent.right = son.left;
son.left.parent = t.parent;
}
son.left.parent = null;
connect34(t, son.left, son, t.left, son.left.left, son.left.right, son.right);
UpdateHeight_BFC(t);
UpdateHeight_BFC(son);
break;
}
}
}
t = t.parent;
}
}
public void Insert(Key key, Value val) {
if (root == null) {
root = new Node(key, val, 0, null, 0);
return;
}
Node temp = root;
while (true) {
int cmp = key.compareTo(temp.key);
if (cmp < 0) {
if (temp.left == null) {
temp.left = new Node(key, val, 0, temp, 0);
UpdateHeight_BFC(temp);
ReBalance(temp);
return;
} else
temp = temp.left;
} else if (cmp > 0) {
if (temp.right == null) {
temp.right = new Node(key, val, 0, temp, 0);
UpdateHeight_BFC(temp);
ReBalance(temp);
return;
} else
temp = temp.right;
} else {
temp.val = val;
return;
}
}
}
public void Remove(Key key) {
Node temp_root = root;
if (root == null || key == null)
return;
while (temp_root != null) {
int cmp = key.compareTo(temp_root.key);
if (cmp > 0)
temp_root = temp_root.right;
else if (cmp < 0)
temp_root = temp_root.left;
else {
if (temp_root.left == null || temp_root.right == null) {
if (temp_root.left != null) {
temp_root.key = temp_root.left.key;
temp_root.val = temp_root.left.val;
temp_root.left = temp_root.left.left;
temp_root.right = temp_root.left.right;
} else if (temp_root.right != null) {
System.out.println(" ");
temp_root.key = temp_root.right.key;
temp_root.val = temp_root.right.val;
temp_root.left = temp_root.right.left;
temp_root.right = temp_root.right.right;
} else {
temp_root = temp_root.parent;
if (temp_root.left != null && temp_root.left.key == key)
temp_root.left = null;
else
temp_root.right = null;
}
UpdateHeight_BFC(temp_root);
ReBalance(temp_root);
} else {
Node t = temp_root.right;
while (t.left != null)
t = t.left;
temp_root.key = t.key;
temp_root.val = t.val;
if (t.right != null) {
t.key = t.right.key;
t.val = t.right.val;
t.left = t.right.left;
t.right = t.right.right;
} else {
t.parent.left = null;
}
UpdateHeight_BFC(t);
ReBalance(t);
}
}
}
}
public static void main(String args[]) {
BBST<Integer, Integer> t = new BBST<Integer, Integer>();
t.Insert(50, 1);
t.Insert(60, 4);
t.Insert(40, 2);
t.Insert(30, 3);
t.Remove(60);
System.out.println("断点设置处");
}
}
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