C语言求二叉树以元素值为x的节点为根的子树深度代码

以下是C语言求二叉树以元素值为x的节点为根的子树深度的代码实现：

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

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

int subtreeDepth(TreeNode* root, int x) {
    if (root == NULL) {
        return 0;
    }
    if (root->val == x) {
        return maxDepth(root);
    }
    int leftDepth = subtreeDepth(root->left, x);
    int rightDepth = subtreeDepth(root->right, x);
    return leftDepth > rightDepth ? leftDepth : rightDepth;
}

int maxDepth(TreeNode* root) {
    if (root == NULL) {
        return 0;
    }
    int leftDepth = maxDepth(root->left);
    int rightDepth = maxDepth(root->right);
    return leftDepth > rightDepth ? leftDepth + 1 : rightDepth + 1;
}

int main() {
    // 构建二叉树
    TreeNode* root = (TreeNode*)malloc(sizeof(TreeNode));
    root->val = 1;
    root->left = (TreeNode*)malloc(sizeof(TreeNode));
    root->left->val = 2;
    root->left->left = NULL;
    root->left->right = NULL;
    root->right = (TreeNode*)malloc(sizeof(TreeNode));
    root->right->val = 3;
    root->right->left = (TreeNode*)malloc(sizeof(TreeNode));
    root->right->left->val = 4;
    root->right->left->left = NULL;
    root->right->left->right = NULL;
    root->right->right = NULL;

    int x = 3;
    int depth = subtreeDepth(root, x);
    printf("Subtree depth for node with val %d is %d\n", x, depth);

    return 0;
}

该代码实现了一个查找二叉树中以元素值为x的节点为根的子树深度的函数subtreeDepth，并且使用了maxDepth函数来计算最大深度。如果节点查找失败或者树为空，subtreeDepth函数会返回0。