SpliBST

SplitBST

It's a premium problem. So it's not tested;

Solution:

vector<TreeNode*> SplitBST(TreeNode* root, int V)
{
  vector<TreeNode*> ans (2, nullptr)

  if(root == nullptr) return ans;

  int x = root->val > V ? 1 : 0;
  int y = root->val > V ? 0 : 1;
  auto& node = root->val > V ? root->left : root->right;
  ans[x] = root;
  auto t = SplitBST(node, V);
  node = t[x];
  ans[y] = t[y];
  return ans;
}

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