树-二叉树的创建和交换二叉树的左右子树C语音

1. 创建二叉树：

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

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

// 创建二叉树
TreeNode* createTree() {
    int val;
    scanf("%d", &val);
    if (val == -1) {
        return NULL;
    }
    TreeNode* root = (TreeNode*)malloc(sizeof(TreeNode));
    root->val = val;
    root->left = createTree();
    root->right = createTree();
    return root;
}

int main() {
    printf("请输入树的节点，-1表示空节点：\n");
    TreeNode* root = createTree();
    return 0;
}

2. 交换二叉树的左右子树：

void invertTree(TreeNode* root) {
    if (root == NULL) {
        return;
    }
    TreeNode* tmp = root->left;
    root->left = root->right;
    root->right = tmp;
    invertTree(root->left);
    invertTree(root->right);
}