树形结构打印二叉搜索树

之前打印二叉树的时候，创建的二叉树是一颗完全平衡的二叉树，对于不平衡的树打印会出现错误，今天又重新改了一下，样子也改进了点，可以打印不平衡的二叉树，算法主要采用中序遍历和层次遍历（广度优先遍历）。

下面是几张效果图：

   ____________________40_______                                        
   |                           |                                        
 __7____                      _73________________________               
 |     |                      |                         |               
_4_   _15_______          ___71             ____________105_            
| |   |        |          |                 |              |            
2 6 _11       _31___     61_          _____91___           105_         
    |         |    |       |          |        |              |         
    9     ___25   _38_     69       _81_      _100_           107_      
          |       |  |              |  |      |   |              |      
         16_     34  39           _79  81_   92   101_           107_   
           |                      |      |           |              |   
           19                    73      90          102            122 

                          _____75_____________                            
                          |                  |                            
                  _______64_      ___________99____________               
                  |        |      |                       |               
    _____________59_____   67_   82_____        __________115_______      
    |                  |     |         |        |                  |      
 __32___            ___62    72       _89_     99_                _118_   
 |     |            |                 |  |       |                |   |   
_2_   _37_         59_              _84  95_     100_          _117   121 
| |   |  |           |              |      |        |          |          
1 7  35  39_         61            82      98       103_     115          
           |                                           |                  
           40_                                         109                
             |                                                            
             44_                                                          
               |                                                          
               46                                                         

代码如下：

//binary_tree.h
struct binary_tree_node{
    int level;
    int value;
    int pre_space;
    binary_tree_node* p_left;
    binary_tree_node* p_right;
};

struct bst_node{
    int value;
    struct bst_node* l;
    struct bst_node* r;
};

binary_tree_node* copy_binary_tree(bst_node* p_bst_root);
void copy_binary_tree_recursively(binary_tree_node* p_node, bst_node* p_bts_node);

binary_tree_node* create_binary_tree_node(int value);
void destroy_binary_tree(binary_tree_node* p_root);

binary_tree_node* create_binary_tree_auto();
void create_binary_tree_recursively(binary_tree_node* p_node);//generate two son nodes, when pass into one node

int get_random_num();

//binary_tree.cpp
#include <stdio.h>
#include "binary_tree.h"
#include <stdlib.h>
#include <time.h>

int g_random_index=0;

binary_tree_node* create_binary_tree_node(int value,int level){
    binary_tree_node* p_node = new binary_tree_node();
    p_node->value = value;
    p_node->level = level;
    p_node->pre_space = 0;
    p_node->p_left = NULL;
    p_node->p_right = NULL;

    return p_node;
}

void destroy_binary_tree(binary_tree_node* p_root)
{
    if(p_root != NULL)
    {   
        binary_tree_node* p_left = p_root->p_left;
        binary_tree_node* p_right = p_root->p_right;

        delete p_root;
        p_root = NULL;

        destroy_binary_tree(p_left);
        destroy_binary_tree(p_right);
    }   
}

int get_random_num(){
    if(g_random_index < 1){
        srand((int)time(NULL));
        g_random_index ++;
    }
    int number = (int)(rand()%321);
    return number;
}

//根据一个标准的二叉树来复制打印的树结构
binary_tree_node* copy_binary_tree(bst_node* p_bst_root){
    int value = p_bst_root->value; 
    binary_tree_node* p_root = create_binary_tree_node(value,1);
    copy_binary_tree_recursively(p_root,p_bst_root);
    return p_root;
}

void copy_binary_tree_recursively(binary_tree_node* p_node, bst_node* p_bst_node){
    int level = p_node->level;

    if(p_bst_node->l != NULL){//left node is not null
        int value_left = p_bst_node->l->value;
        binary_tree_node* p_left = create_binary_tree_node(value_left,level+1);
        p_node->p_left = p_left;
        copy_binary_tree_recursively(p_left, p_bst_node->l);
    }

    if(p_bst_node->r != NULL){
        int value_right = p_bst_node->r->value;
        binary_tree_node* p_right = create_binary_tree_node(value_right,level+1);
        p_node->p_right = p_right;
        copy_binary_tree_recursively(p_right, p_bst_node->r);
    }
}

//print_binary_tree.h
void print_binary_tree(bst_node* p_bst_root);

//print_binary_tree.cpp

#include <stdio.h>
#include "binary_tree.h"
#include <deque>
#include <iostream>
#include <string> //处理字符串
#include <string.h> //处理字符串
using namespace std;

int g_spaces = 0;

int calc_characters(int value){
    if(value == 0){
        return 1;
    }
    int characters = 0;
    while(value){
        characters ++;
        value = value/10;
    }
    return characters;
}

struct str_n{
    string str;
    string str_pointer;
};


struct str_n* set_string_node(string str, string str_pointer, binary_tree_node* p_node){
    //set value
    int value_pos = p_node->pre_space;
    char ch[10];
    sprintf(ch,"%d",p_node->value);
    str.replace(value_pos,strlen(ch),ch);

    //set vertical line
    string vertical_l;
    string vertical_r;

    //set underline left
    int underline_length_left = 0;
    int underline_index_left = 0;
    int vertical_left_length = 0;
    if(p_node->p_left != NULL){
        underline_length_left = p_node->pre_space 
            - p_node->p_left->pre_space 
            - calc_characters(p_node->p_left->value) + 1;
        underline_index_left = p_node->p_left->pre_space 
            + calc_characters(p_node->p_left->value) - 1;
        vertical_left_length = 1;
        vertical_l.assign(1,'|');
    }
    string str_underline_left(underline_length_left,'_');
    str.replace(underline_index_left,underline_length_left,str_underline_left);
    str_pointer.replace(underline_index_left,vertical_left_length,vertical_l);

    //set underline right
    int underline_length_right = 0;
    int underline_index_right = 0;
    int vertical_right_length = 0;
    int vertical_right_index = 0;
    if(p_node->p_right != NULL){
        underline_length_right = p_node->p_right->pre_space 
            - p_node->pre_space 
            -calc_characters(p_node->value) + 1;
        underline_index_right = p_node->pre_space + calc_characters(p_node->value);
        vertical_right_length = 1;
        vertical_right_index = underline_index_right+underline_length_right-1;
        vertical_r.assign(1,'|');
    }
    string str_underline_right(underline_length_right,'_');
    str.replace(underline_index_right,underline_length_right,str_underline_right);
    str_pointer.replace(vertical_right_index,vertical_right_length,vertical_r);

    struct str_n* p_str_n = new str_n();
    p_str_n->str = str;
    p_str_n->str_pointer = str_pointer;

    return p_str_n;
}

int g_currunt_level = 1;

void print_from_top_to_bottom(binary_tree_node* p_root)
{
    if(p_root == NULL)
        return;

    //队列
    std::deque<binary_tree_node *> deque_tree_node;

    deque_tree_node.push_back(p_root);

    string str_node(g_spaces+1,' ');
    string str_node_pointer(g_spaces+1,' ');
    //cout << string << endl;
    while(deque_tree_node.size())
    {
        binary_tree_node* p_node = deque_tree_node.front();//从前面获取结点
        deque_tree_node.pop_front();//之后将其弹出

        if(p_node->level == g_currunt_level){
            struct str_n* p_str_n = set_string_node(str_node, str_node_pointer, p_node);
            str_node = p_str_n->str;
            str_node_pointer = p_str_n->str_pointer;
        }
        if(p_node->level > g_currunt_level){
            //output str_node and then set str_node to empty
            cout << str_node << endl;
            cout << str_node_pointer << endl;
            str_node.assign(g_spaces+1,' ');
            str_node_pointer.assign(g_spaces+1,' ');
            g_currunt_level = p_node->level;
            struct str_n* p_str_n = set_string_node(str_node, str_node_pointer, p_node);
            str_node = p_str_n->str;
            str_node_pointer = p_str_n->str_pointer;
        }

        //do_print_binary_tree(p_node);

        //先压入左结点
        if(p_node->p_left)
            deque_tree_node.push_back(p_node->p_left);

        //后压入右结点
        if(p_node->p_right)
            deque_tree_node.push_back(p_node->p_right);
    }   
    cout << str_node << endl;
    g_currunt_level = 1;//这个很重要，之前没有设置害的我只能打印一次
    g_spaces = 0;
    printf("
");
}

void in_order(binary_tree_node* p_node){
    if(p_node->p_left!=NULL){
        in_order(p_node->p_left);
    }
    //Do Something with root
    p_node->pre_space = g_spaces;
    g_spaces += calc_characters(p_node->value);
    //printf("%d(%d)	",p_node->value,p_node->pre_space);
    if(p_node->p_right!=NULL){
        in_order(p_node->p_right);
    }
}

void print_binary_tree(bst_node* p_bst_root){
    struct binary_tree_node* p_root = copy_binary_tree(p_bst_root);
    in_order(p_root);
    print_from_top_to_bottom(p_root);
}

//BST.cpp

#include <malloc.h>
#include <iostream>
#include "binary_tree.h"
#include "print_binary_tree.h"
//the node of a tree, included in binary_tree.h
#include <stdlib.h>
#include <time.h>
using namespace std;

//create node with value, left child and right child 
struct bst_node* create_bst_node(int value, struct bst_node* l, struct bst_node* r){
    struct bst_node* t =(struct bst_node*) malloc(sizeof *t);//should call free() when finished
    t->value = value;
    t->l = l;
    t->r = r;
    return t;
}

struct bst_node* bst_insert(struct bst_node* root, int value){
    if(root == NULL) 
        return create_bst_node(value,NULL,NULL);//tree is empty
    //if root is not NULL
    if(value < root->value)
        root->l = bst_insert(root->l,value);//insert into left child
    else if (value >= root->value)
        root->r = bst_insert(root->r,value);//
    return root;
}

int main(){
    //create_bst_node();
    srand((unsigned)time(NULL));//使用系统时间初试化随机种子
    int value = rand()%123;
    struct bst_node* bst_root = create_bst_node(value, NULL, NULL);
    for(int k=0; k<33; k++){
        value = rand()%123;
        bst_insert(bst_root, value);
    }

    print_binary_tree(bst_root);

    return 0;
}