二叉树的部分操作（递归）

二叉树的部分操作。前序、中序、后序遍历，节点个数、k层节点个数、查找、叶子节点个数、二叉树高度

#pragma once
#include<stdio.h>
#include<stdlib.h>
#include<assert.h>
#include<stdbool.h>

typedef int DataType;
typedef struct Node{
    DataType val;
    struct Node* left;
    struct Node* right;
};

typedef struct BinaryTree{

    Node* root;

}BinaryTree;

//初始化
void InitBinaryTree(BinaryTree * root)
{
    root == NULL;
}

//前序遍历
void preOrderTraversal(Node* root)
{
    if (NULL == root)
        return;
    printf("%d  ", root->val);
    preOrderTraversal(root->left);
    preOrderTraversal(root->right);

}

//中序遍历
void inOrderTraversal(Node* root)
{
    if (NULL == root)
        return;
    inOrderTraversal(root->left);
    printf("%d  ", root->val);
    inOrderTraversal(root->right);

}

//后序遍历
void postOrderTraversal(Node* root)
{
    if (NULL == root)
        return;
    postOrderTraversal(root->left);
    postOrderTraversal(root->right);
    printf("%d  ", root->val);

}

//节点个数
int count = 0;
void getcount1(Node* root)
{
    if (NULL == root)
        return;
    count++;
    getcount1(root->left);
    getcount1(root->right);
}

//节点个数
int getcount2(Node* root)
{
    if (NULL == root)
        return 0;
    
    int left = getcount2(root->left);
    int right = getcount2(root->right);
    return left + right + 1;
}


int myMax(int a, int b)
{
    return (a > b ? a:b);
}
//二叉树高度
int getHight(Node * root)
{
    if (NULL == root)
        return 0;
    int left = getHight(root->left);
    int right = getHight(root->right);
    return myMax(left, right)+1;

}

//统计二叉树叶子节点
int getLeafCount(Node* root)
{
    if (NULL == root)
        return 0;
    else if (NULL == root->left  && NULL ==root->right)
        return 1;
    else
    {
        int left = getLeafCount(root->left);
        int right = getLeafCount(root->right);
        return left + right;
    }
}

//二叉树第k层节点个数
int getKLeveCount(Node * root,int k)
{
    assert(k >= 1);
    if (NULL == root)
        return 0;
    else if (1 == k)
        return 1; 
    else
    {
        int left = getKLeveCount(root->left, k - 1);
        int right = getKLeveCount(root->right, k - 1);
        return left + right;
        //return getKLeveCount(root->left, k - 1)+ getKLeveCount(root->right, k - 1);
    }
}

//在二叉树中查找值为V的节点
Node* Find(Node* root,int v)
{
    if (NULL == root)
        return NULL;
    if (v == root->val)
        return root;
    else
    {
        Node* FindLeft = Find(root->left,v);
        if (FindLeft != NULL){
            return FindLeft;
        }
        Node* FindRight = Find(root->right, v);
        if (FindRight != NULL){
            return FindRight;
        }
        else{
            return NULL;
        }
    }
}