算法导论 数据扩张
在红黑树的基础上扩张,额外增加一个的信息(包含当前节点子树的所有节点数量),使其功能更加强大,能够轻松访问每个元素在数组中的排列位置,
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#define _CRT_SECURE_NO_WARNINGS#include <stdio.h>
#include<malloc.h>
//*********************************以下内容是插入源码****************************
#define N 10
#define K 100
typedef struct redblacknode RBN;
struct redblacknode {//红黑树的节点
int key;
char rb;
RBN* father;
RBN* left;
RBN* right;
int size;
};
void redblacktree(RBN* p, int key);//红黑树,能插入关键字
void happen_rand(int* p, int n);//生成随机数
void color(RBN* p);
void right_handed(RBN* p);//右旋
void left_handed(RBN* p);//左旋
RBN sentry={-1,'b',&sentry,&sentry,&sentry };//哨兵,主要作用是节省空间,不然每一个叶节点都要开辟一个空结构体;详见算法导论10.2的介绍
RBN *uncle;//定义一个叔叔指针
RBN* NODE;//定义一个根节点指针
RBN* tmp,*tmptmp;
void happen_rand(int* p, int n) {
int i;
for (i = 0; i < N; i++) {
p[i] = rand() % K;
}
}
void redblacktree(RBN* p, int key) {//递归的方式把key插入到红黑树中
if (key < p->key && p->left == &sentry) {//插入节点后需要用color函数调整颜***r /> p->left = (RBN*)malloc(sizeof(RBN));
p->left->key = key;
p->left->father = p;
p->left->left = &sentry;
p->left->right = &sentry;
p->left->rb = 'r';
color(p->left);
}
else if (key >= p->key && p->right == &sentry) {
p->right = (RBN*)malloc(sizeof(RBN));
p->right->key = key;
p->right->father = p;
p->right->left = &sentry;
p->right->right = &sentry;
p->right->rb = 'r';
color(p->right);
}
else if (key < p->key && p->left != &sentry)
redblacktree(p->left, key);
else if (key >= p->key && p->right != &sentry)
redblacktree(p->right, key);
p->size++;
while (p != NODE) {
p = p->father;
p->size--;
}
}
void color(RBN* p) {//颜色调整分为6种状态,前两种不旋转直接调色,后四种要旋转,旋转后再调色,旋转有4种状态,每一种状态旋转后需要调色(176页)(/右旋)(\左旋)(<左旋+/右旋)(>右旋+\左旋)
if (p->rb == 'b') { return; }
if (p->father->rb == 'r') {
if (p->father == p->father->father->left) {//父节点是左节点
uncle = p->father->father->right;//叔节点是右节点
if (uncle->rb == 'r') {//叔节点是红
if (p->father->father->father != &sentry)p->father->father->rb = 'r';
p->father->rb = 'b';
uncle->rb = 'b';
color(p->father->father);
}
else if (uncle->rb == 'b' || uncle == &sentry) {//叔节点是黑或者是无
if (p == p->father->left) {//插入节点是左,进行右旋,变***r /> right_handed(p->father);
p->father->rb = 'b';
p->father->right->rb = 'r';
color(p->father);
}
else if (p == p->father->right) {//插入节点是右,进行左旋,右旋,变***r /> left_handed(p);
right_handed(p);
p->rb = 'b';
p->right->rb = 'r';
color(p);
}
}
}
else if (p->father == p->father->father->right) {//父节点是右节点
uncle = p->father->father->left;//叔节点是左节点
if (uncle->rb == 'r') {//叔节点是红
if (p->father->father->father != &sentry)p->father->father->rb = 'r';
p->father->rb = 'b';
uncle->rb = 'b';
color(p->father->father);
}
else if (uncle->rb == 'b' || uncle == &sentry) {//叔节点是黑或者是无
if (p == p->father->right) {//插入节点是右,进行左旋,变***r /> left_handed(p->father);
p->father->rb = 'b';
p->father->left->rb = 'r';
color(p->father);
}
else if (p == p->father->left) {//插入节点是左,进行右旋,左旋,左旋
right_handed(p);
left_handed(p);
p->rb = 'b';
p->left->rb = 'r';
color(p);
}
}
}
}
}
void left_handed(RBN* p) {
int tmp;
RBN* y = p;
RBN* x = y->father;
x->right = y->left;
if (y->left != &sentry) y->left->father = x;
y->father = x->father;
if (x->father == &sentry) NODE = y;
else if (x == x->father->left) x->father->left = y;
else x->father->right = y;
y->left = x;
x->father = y;
tmp = x->size;
x->size = y->size;
y->size = tmp;
}
void right_handed(RBN* p) {
int tmp;
RBN* x = p;
RBN* y = x->father;
y->left = x->right;
if (x->right != &sentry) x->right->father = y;
x->father = y->father;
if (y->father == &sentry) NODE = x;
else if (y == y->father->left) y->father->left = x;
else y->father->right = x;
x->right = y;
y->father = x;
tmp = x->size;
x->size = y->size;
y->size = tmp;
}
//*********************************以上内容是插入源码****************************
//;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
//*********************************以下内容是按层打印源码****************************
typedef struct queue SQ;//队列
struct queue {
RBN array[N];
RBN* head;
RBN* tail;
};//申明队列结构体
int enqueue(SQ* p, RBN n);//入队
RBN* dequeue(SQ* p);//出队
int printf_tree_layer(RBN* p);//按层遍历打印二叉树
int enqueue(SQ* p, RBN n) {
*p->tail = n;
p->tail++;
if (p->tail == &p->array[N]) {
p->tail = &p->array[0];
}//尾部循环
if (p->head == p->tail)//判断溢出
return -1;
}
RBN* dequeue(SQ* p) {
if (p->head == &p->array[N]) {
p->head = &p->array[0];
}//尾部循环
if (p->head == p->tail) //判断溢出
{
RBN* p = NULL;
return p;
}
return (p->head++);
}
SQ Q = { {0},&Q.array[0],&Q.array[0] };//Q队列初始化
int k = 0;
int sumup = 1;//当前行的元素个数
int sumdown = 0;//下一行的元素个数
int printf_tree_layer(RBN* p) {
if (p == &sentry) { printf("not number"); return; }
if (0 == sumup) {//这里是关键,当前元素是0的时候换行,
if (sumdown == 0) { printf("\n"); sumdown = 1; return; }//判断下一行是否为0
printf("\n");
sumup = sumdown;
sumdown = 0;
}
printf("%d ", p->key);
sumup--;//每次打印后当前元素个数减一
if (&sentry != p->left) { enqueue(&Q, *p->left); sumdown++; }//每次生成子元素后下一行元素个数加一
if (&sentry != p->right) { enqueue(&Q, *p->right); sumdown++; }//每次生成子元素后下一行元素个数加一
RBN* T = dequeue(&Q);
printf_tree_layer(T);
}
//*********************************以上内容是按层打印源码****************************
//;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
//*********************************以下内容是删除源码****************************
RBN* y,*x;//记录将要被删除(或者是后继节点)的和替补的结构体的地址
char y_color;///记录将要被删除的结构体的颜***r /> void rb_transplant(RBN* father, RBN* son);//儿子移动到父亲的位置
RBN* rb_delete(RBN *p);//删除p节点
RBN* address(RBN*p,int key);//通过关键字,找地址,
RBN* tree_minsum(RBN* p);//找到后继(该节点的右子树的最小元素)
RBN* cut_out_color_fixup(RBN* x);//删除后,保持平衡
RBN* cut_out_color_fixup(RBN* x) {
RBN* w; //兄弟节点
while (x != NODE && x->rb == 'b') {//y是黑色,x也是黑色,x就是双黑节点(被移动的节点是黑色,替补上去的也是黑色,叫做双黑非根节点)
if (x == x->father->left) {
w = x->father->right;//兄弟节点
if (w->rb == 'r') {//四种状态,详见算法导论186页
w->rb = 'b';
x->father->rb = 'r';
left_handed(w);
w = x->father->right;
}
if (w->left->rb == 'b' && w->right->rb == 'b') {
w->rb = 'r';
x = x->father;
continue;
}
else if (w->right->rb == 'b') {
w->left->rb = 'b';
w->rb = 'r';
right_handed(w->left);
w = x->father->right;
}
w->rb = x->father->rb;
x->father->rb = 'b';
w->right->rb = 'b';
left_handed(w);
x = NODE;
}
else {
w = x->father->left;//兄弟节点
if (w->rb == 'r') {
w->rb = 'b';
x->father->rb = 'r';
right_handed(w);
w = x->father->left;
}
if (w->left->rb == 'b' && w->right->rb == 'b') {
w->rb = 'r';
x = x->father;
continue;
}
else if (w->left->rb == 'b') {
w->right->rb = 'b';
w->rb = 'r';
left_handed(w->right);
w = x->father->left;
}
w->rb = x->father->rb;
x->father->rb = 'b';
w->left->rb = 'b';
right_handed(w);
x = NODE;
}
}
x->rb = 'b';
}
RBN* tree_minsum(RBN* p)
{
while (p->left != &sentry) {
p = p->left;
}
return p;
}
void rb_transplant(RBN* father, RBN* son) {
son->size = father->size;
if (father->father == &sentry) {
NODE = son;
}
else if (father == father->father->left) {
father->father->left = son;
}
else {
father->father->right = son;
}
son->father = father->father;
}
RBN* address(RBN*p,int key) {
if (key == p->key) return p;
if (p == &sentry)return &sentry;
if (key < p->key)
address(p->left, key);
else
address(p->right, key);
}
RBN* rb_delete(RBN* z) {
y = z;
y_color = y->rb;
if (z->left == &sentry) {
x = z->right;
rb_transplant(z, z->right);
}
else if(z->right == &sentry) {
x = z->left;
rb_transplant(z, z->left);
}
else {
y = tree_minsum(z->right);
y_color = y->rb;
x = y->right;
if (y->father == z){//后继节点是z的右孩子
x->father = y;
}
else { //将后继节点y取出,放到z的右孩子的父节点
rb_transplant(y, y->right);
y->right = z->right;
y->right->father = y;
}
rb_transplant(z, y);
y->left = z->left;
y->left->father = y;
y->rb = z->rb;//保持原有的平衡
}
x->size = y->size - 1;
while (x != NODE) {
x = x->father;
x->size --;
}
if (y_color == 'b') {//y是红色,必然没有孩子,直接删除后,无需调整颜色,y是黑色,删除后需要调整颜***r /> cut_out_color_fixup(x);
}
}
//*********************************以上内容是删除源码****************************
//;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
//*********************************以下内容是扩张源码****************************
int r=0,R=0;//记录当前点的秩
int size_result(RBN* p) {
if (p == &sentry) return 0;
if (p->left == &sentry && p->right == &sentry){
p->size = 1;
return 1;
}
else
return p->size = size_result(p->left) + size_result(p->right)+1;
}
RBN* os_select(RBN*x, int i);//找到第i小关键字的结构体
int os_rank(RBN* x);//找到x的秩
RBN* os_select(RBN* x, int i) {
if (x == &sentry)
return &sentry;
r = x->left->size + 1;
if (r == i)
return x;
if (i < r)
os_select(x->left, i);
else
os_select(x->right, i - r);
}
int os_rank(RBN* x) {
RBN* X = NODE;
int r = 0;
while (x!=X) {
if (x->key < X->key)
X = X->left;
else {
r = r + 1 + X->left->size;
X=X->right;
}
}
r = r + 1 + x->left->size;
return r;
}
//在对红黑树删除和插入时,会影响它的秩,该部分代码,直接修改插入和删除函数(x点的size减一,并且一直往上走,每个点减一,到跟停止)
//*********************************以上内容是扩张源码****************************
int I=1;//秩
int main() {
int array[N] = { 0}, i;
happen_rand(array, N);//数组随机化
RBN node = { array[0],'b' ,&sentry,&sentry,&sentry };//根节点
NODE = &node;
for (i = 1; i < N; i++) {
redblacktree(NODE, array[i]);//在红黑树中插入元素
}
printf_tree_layer(NODE);
printf("\n");
size_result(NODE);
printf("%d\n",os_select(NODE,I)->key);
for (int i = 0; i < N; i++) {
RBN* tmp = address(NODE, array[i]);
printf("%d %d\n", tmp->key,os_rank(tmp));//通过关键字找到秩
printf("%d %d\n", os_select(NODE, os_rank(tmp))->key, os_rank(tmp));//通过秩找到关键字
}
for (i = 0; i < N; i++) {
RBN* tmp = address(NODE,array[i] );
rb_delete(tmp);//在红黑树中删除元素
printf_tree_layer(NODE);
}
}
算法导论 文章被收录于专栏
以小白的角度诠释算法导论,假如有人看不懂,我就面壁思过。