C语言编写二叉树的遍历

以下是C语言编写二叉树的三种遍历方式的例子：

1.前序遍历（根-左-右）

#include <stdio.h>
#include <stdlib.h>

struct TreeNode {
    int val;
    struct TreeNode *left;
    struct TreeNode *right;
};

void preorderTraversal(struct TreeNode* root){
    if(root == NULL) return;
    printf("%d ", root->val);
    preorderTraversal(root->left);
    preorderTraversal(root->right);
}

2.中序遍历（左-根-右）

#include <stdio.h>
#include <stdlib.h>

struct TreeNode {
    int val;
    struct TreeNode *left;
    struct TreeNode *right;
};

void inorderTraversal(struct TreeNode* root){
    if(root == NULL) return;
    inorderTraversal(root->left);
    printf("%d ", root->val);
    inorderTraversal(root->right);
}

3.后序遍历（左-右-根）

#include <stdio.h>
#include <stdlib.h>

struct TreeNode {
    int val;
    struct TreeNode *left;
    struct TreeNode *right;
};

void postorderTraversal(struct TreeNode* root){
    if(root == NULL) return;
    postorderTraversal(root->left);
    postorderTraversal(root->right);
    printf("%d ", root->val);
}