除了删除节点之外，把红黑树基本上看完了，顺手用java实现了一棵红黑树
import javax.swing.*;/** * Created by eminem on 16-11-15. */public class brTree { private Node root; private static final boolean RED = true; private static final boolean BLACK = false; private class Node { String key; int value; Node left, right; int N; boolean color; public Node(String key, int value, int N, boolean color) { this.key = key; this.value = value; this.N = N; this.color = color; } } private boolean isRed(Node x) { //空链接那么他就是black if (x == null) return false; return x.color == RED; } int size(Node shit) { if (shit == null) return 0; else return shit.N; } Node rotateLfet(Node h) { Node x = h.right; h.right = x.left; x.left = h; x.color = h.color; h.color = RED; x.N = h.N; h.N = size(h.left) + size(h.right) + 1; return x; } Node rotateRight(Node h) { Node x = h.left; h.left = x.right; x.right = h; x.color = h.color; h.color = RED; x.N = h.N; h.N = size(h.left) + size(h.right) + 1; return x; } private void flipColors(Node shit) { shit.color = RED; shit.left.color = BLACK; shit.right.color = BLACK; } public void put(String key, int value) { root = put(root, key, value); root.color = BLACK; } private Node put(Node shit, String key, int value) { if (shit == null) { return new Node(key, value, 1, RED); } int cmp = key.compareTo(shit.key); if (cmp < 0) shit.left = put(shit.left, key, value); else if (cmp > 0) shit.right = put(shit.right, key, value); else shit.value = value; if (isRed(shit.right) && !isRed(shit.left)) shit = rotateLfet(shit); if (isRed(shit.left) && isRed(shit.left.left)) shit = rotateRight(shit); if (isRed(shit.left) && isRed(shit.right)) flipColors(shit); shit.N = size(shit.left) + size(shit.right) + 1; return shit; } public int get(String key) { return get(root, key); } private Integer get(Node x, String key) { if (x == null) return null; int cmp = key.compareTo(x.key); if (cmp > 0) { return get(x.right, key); } else if (cmp < 0) { return get(x.left, key); } else { return x.value; } } public String min() { return min(root).key; } private Node min(Node x) { if (x.left == null) return x; return min(x.left); } public String max() { return max(root).key; } private Node max(Node x) { if (x.right == null) return x; return max(x.right); } public String floor(String key) { Node x = floor(root, key); if (x == null) return null; return x.key; } private Node floor(Node x, String key) { if (x == null) return null; int cmp = key.compareTo(x.key); if (cmp == 0) return x; if (cmp < 0) return floor(x.left, key); Node t = floor(x.right, key); if (t != null) return t; else return x; } //找到排名为k的键 public String select(int k) { return select(root, k).key; } private Node select(Node x, int k) { if (x == null) return null; int t = size(x.left); if (t > k) return select(x.left, k); else if (t < k) return select(x.right, k - t - 1); else return x; } public int rank(String key) { return rank(root, key); } private Integer rank(Node x, String key) { //始终没命中，已到树的末尾 if (x == null) return 0; int cmp = key.compareTo(x.key); if (cmp < 0) return rank(x.left, key); else if (cmp > 0) return 1 + size(x.left) + rank(x.right ,key); else return size(x.left); }}//md这些算法的发明者也是吊，怎么想出来的啊这东西
测试类如下：
/** * Created by eminem on 16-11-17. */public class brTestt { public static void main(String[] args) { brTree fuck=new brTree(); fuck.put("a",1); fuck.put("b",2); fuck.put("c",3); fuck.put("d",4); fuck.put("e",5); fuck.put("f",6); fuck.put("g",7); fuck.put("h",8); System.out.println(fuck.select(7)); System.out.println(fuck.get("a")); System.out.println(fuck.floor("o")); }}
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