LeetCode 450. 删除二叉搜索树中的节点
原题链接
中等
作者:
大明湖的鱼
,
2021-01-30 11:51:10
,
所有人可见
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阅读 339
/**
* Definition for a binary tree node.
* struct TreeNode {
* int val;
* TreeNode *left;
* TreeNode *right;
* TreeNode() : val(0), left(nullptr), right(nullptr) {}
* TreeNode(int x) : val(x), left(nullptr), right(nullptr) {}
* TreeNode(int x, TreeNode *left, TreeNode *right) : val(x), left(left), right(right) {}
* };
*/
class Solution {
public:
TreeNode* deleteNode(TreeNode* root, int key) {
if(root == nullptr) return nullptr;
if(key > root->val) root->right =deleteNode(root->right,key);//去右子树删除
else if(key < root->val) root->left = deleteNode(root->left,key);
else {
if(root->left == nullptr) return root->right;
if(root->right == nullptr) return root->left;
TreeNode* node = root->right;
while(node->left){
node = node->left; //寻找欲删除节点右子树的最左节点
}
node->left = root->left; //将欲删除节点的左子树成为其右子树的最左节点的左子树
root = root->right; //欲删除节点的右子树顶替其位置
}
return root;
}
};