//树的链式存储--二叉表示法
#include<stdio.h>
#include<stdlib.h>
#include<string.h>typedef struct _TreeNode{//数据域int data;//指针域struct _TreeNode * leftchild;//左孩子指针struct _TreeNode * rightchild;//右孩子指针
}TreeNode, *TreeNodePointer;/*
以上语法定义了两个类型
第一个是typedef struct _TreeNode TreeNode 树的节点类型
第二个是typedef struct _TreeNode * TreeNodePointer 树的指针类型定义了一个结构体
typedef struct _TreeNode{
int data;
struct _TreeNode * leftchild;
struct _TreeNode * rightchild;
};
重命名 typedef struct _TreeNode TreeNode
定义一个指针类型 typedef struct _TreeNode * TreeNodePointer
注意：struct _TreeNode *这才是指针类型，TreeNodePointer是类型的名字
*/void Test1(){//定义结构体对象
    TreeNode t1, t2, t3, t4, t5;//填充数据域t1.data = 1;t2.data = 2;t3.data = 3;t4.data = 4;t5.data = 5;//建立树之间的关系//t1是根节点  t2是t1的左孩子t1.leftchild = &t2;t1.rightchild = NULL;// t3是t2的左孩子t2.leftchild = &t3;t2.rightchild = NULL;// t4是t2的左孩子t3.leftchild = &t4;t3.rightchild = NULL;// t5是t4的左孩子t4.leftchild = &t5;t4.rightchild = NULL;//t5没有孩子节点t5.leftchild = NULL;t5.rightchild = NULL;
}void Test2(){//定义结构体对象TreeNodePointer t1 = NULL, t2 = NULL, t3 = NULL, t4 = NULL, t5 = NULL;t1 = (TreeNodePointer)malloc(sizeof(TreeNode));if (t1==NULL){printf("分配内存失败！");goto END;}//初始化数据memset(t1, 0, sizeof(TreeNode));t2 = (TreeNodePointer)malloc(sizeof(TreeNode));if (t2 == NULL){printf("分配内存失败！");goto END;}//初始化数据memset(t2, 0, sizeof(TreeNode));t3= (TreeNodePointer)malloc(sizeof(TreeNode));if (t3 == NULL){printf("分配内存失败！");goto END;}//初始化数据memset(t3, 0, sizeof(TreeNode));t4 = (TreeNodePointer)malloc(sizeof(TreeNode));if (t4 == NULL){printf("分配内存失败！");goto END;}//初始化数据memset(t4, 0, sizeof(TreeNode));t5 = (TreeNodePointer)malloc(sizeof(TreeNode));if (t5 == NULL){printf("分配内存失败！");goto END;}//初始化数据memset(t5, 0, sizeof(TreeNode));//填充数据域t1->data = 1;t2->data = 2;t3->data = 3;t4->data = 4;t5->data = 5;//建立树之间的关系//t1是根节点  t2是t1的左孩子t1->leftchild = t2;t1->rightchild = NULL;// t3是t2的左孩子t2->leftchild = t3;t2->rightchild = NULL;// t4是t2的左孩子t3->leftchild = t4;t3->rightchild = NULL;// t5是t4的左孩子t4->leftchild = t5;t4->rightchild = NULL;//t5没有孩子节点t5->leftchild = NULL;t5->rightchild = NULL;END:if (t1!=NULL){free(t1);t1 = NULL;}if (t2 != NULL){free(t2);t2 = NULL;}if (t3 != NULL){free(t3);t3 = NULL;}if (t4 != NULL){free(t4);t4 = NULL;}if (t5 != NULL){free(t5);t5 = NULL;}
}void main(){system("pause");
}