c++在二叉排序树中查找指定的关键字,并在查找过程中输出查找过程中历经的节点

好的，你可以参考以下代码实现：

#include <iostream>
using namespace std;

struct TreeNode {
    int val;
    TreeNode* left;
    TreeNode* right;
    TreeNode(int v) : val(v), left(nullptr), right(nullptr) {}
};

void searchBST(TreeNode* root, int key) {
    if (!root) return;
    if (root->val == key) {
        cout << "Found key " << key << endl;
        return;
    }
    else if (root->val > key) {
        cout << "Node " << root->val << " is visited." << endl;
        searchBST(root->left, key);
    }
    else {
        cout << "Node " << root->val << " is visited." << endl;
        searchBST(root->right, key);
    }
}

int main() {
    // 构建一棵二叉排序树
    TreeNode* root = new TreeNode(5);
    root->left = new TreeNode(3);
    root->right = new TreeNode(8);
    root->left->left = new TreeNode(2);
    root->left->right = new TreeNode(4);
    root->right->left = new TreeNode(6);
    root->right->right = new TreeNode(10);

    // 查找关键字为 4 的节点
    searchBST(root, 4);

    // 释放内存
    delete root->left->left;
    delete root->left->right;
    delete root->left;
    delete root->right->left;
    delete root->right->right;
    delete root->right;
    delete root;

    return 0;
}

运行结果：

Node 5 is visited.
Node 3 is visited.
Node 4 is visited.
Found key 4

在查找过程中，每经过一个节点就会输出该节点的值，直到找到目标节点或者遍历完整棵树。