二叉数的遍历实现
时间: 2023-08-15 16:19:52 浏览: 73
二叉树的遍历有三种方式:前序遍历、中序遍历和后序遍历。其中,前序遍历的访问顺序为根结点 -> 左子树 -> 右子树;中序遍历的访问顺序为左子树 -> 根结点 -> 右子树;后序遍历的访问顺序为左子树 -> 右子树 -> 根结点。以下是二叉树遍历的实现代码:
```c++
#include <iostream>
using namespace std;
struct TreeNode {
int val;
TreeNode* left;
TreeNode* right;
TreeNode(int x) : val(x), left(NULL), right(NULL) {}
};
// 前序遍历
void preorderTraversal(TreeNode* root) {
if (root == NULL) return;
cout << root->val << " ";
preorderTraversal(root->left);
preorderTraversal(root->right);
}
// 中序遍历
void inorderTraversal(TreeNode* root) {
if (root == NULL) return;
inorderTraversal(root->left);
cout << root->val << " ";
inorderTraversal(root->right);
}
// 后序遍历
void postorderTraversal(TreeNode* root) {
if (root == NULL) return;
postorderTraversal(root->left);
postorderTraversal(root->right);
cout << root->val << " ";
}
int main() {
TreeNode* root = new TreeNode(1);
root->left = new TreeNode(2);
root->right = new TreeNode(3);
root->left->left = new TreeNode(4);
root->left->right = new TreeNode(5);
cout << "preorderTraversal: ";
preorderTraversal(root);
cout << endl;
cout << "inorderTraversal: ";
inorderTraversal(root);
cout << endl;
cout << "postorderTraversal: ";
postorderTraversal(root);
cout << endl;
return 0;
}
```