TreeNode* upsideDownBinaryTree(TreeNode* root) {
if (!root || !root->left) return root;
TreeNode *newRoot = upsideDownBinaryTree(root->left);
root->left->left = root->right;
root->left->right = root;
root->left = NULL;
root->right = NULL;
return newRoot;
}
TreeNode* upsideDownBinaryTree(TreeNode* root) {
if (root == nullptr || root->left == nullptr) return root;
TreeNode *parent = upsideDownBinaryTree(root->left);
TreeNode *tmp = parent;
while (tmp->right != nullptr) tmp = tmp->right;
tmp->right = root;
tmp->left = root->right;
root->right = root->left = nullptr;
return parent;
}
TreeNode* upsideDownBinaryTree(TreeNode* root) {
if(root==NULL||root->left==NULL)
return root;
TreeNode* left=root->left;
TreeNode* right=root->right;
TreeNode* newRoot=upsideDownBinaryTree(left);
newRoot->right=root;
newRoot->left=right;
root->left=NULL;
root->right=NULL;
return newRoot;
}
