二叉树

二叉树的简单操作函数
主要包括二叉树初始化二叉排序树插入前中后序遍历

#include <stdio.h>
#include <malloc.h>

typedef struct BTNode {
    int data;
    struct BTNode* left;
    struct BTNode* right;
}BTNode;



BTNode* init() {
    BTNode* root = (BTNode*)malloc(sizeof(BTNode));
    root->data = 5;
    root->left = NULL;
    root->right = NULL;
    return root;
}


// 按照二叉排序树 插入树
void insert(BTNode* root, int value) {
    if (value < root->data) {
        if (root->left == NULL) {
            BTNode* node;
            node = (BTNode*)malloc(sizeof(BTNode));
            node->data = value;
            node->left = NULL;
            node->right = NULL;
            root->left = node;
            return;
        }
        insert(root->left, value);
    }
    else
    {
        if (root->right == NULL) {

            BTNode* node;
            node = (BTNode*)malloc(sizeof(BTNode));
            node->data = value;
            node->left = NULL;
            node->right = NULL;
            root->right = node;
            return;

        }
        insert(root->right, value);
    }
};


// 中序打印 
void midPrint(BTNode* root) {
    if (root != NULL) {
        midPrint(root->left);
        printf("%d", root->data);
        midPrint(root->right);
    }
}


// 先序打印 
void prePrint(BTNode* root) {
    if (root != NULL) {
        printf("%d", root->data);
        prePrint(root->left);
        prePrint(root->right);
    }
}
// 后序打印 
void postPrint(BTNode* root) {
    if (root != NULL) {
        postPrint(root->left);
        postPrint(root->right);
        printf("%d", root->data);
    }
}

int main()
{
    int a = 1;
    BTNode* root = init();
    printf("%d\n",root->data);
    for (int i = 1; i <= 8; i++)
    {
         insert(root, i);
    }
    printf("中序遍历\n");
    midPrint(root);
    printf("\n先序遍历\n");
    prePrint(root);
    printf("\n后序遍历\n");
    prePrint(root);
    return 0;
}