leetcode

Solution to some Leetcode problems written in C++
git clone git://git.dimitrijedobrota.com/leetcode.git
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1325.cpp (996B)

      1 class Solution {
      2   public:
      3     TreeNode *removeLeafNodes(TreeNode *root, int target) {
      4         TreeNode dummy(-1, root, nullptr);
      5         unordered_map<TreeNode *, TreeNode *> um = {{root, &dummy}};
      6         stack<TreeNode *> st({root});
      7         while (!st.empty()) {
      8             TreeNode *root = st.top();
      9             if (root->val < 0) {
     10                 st.pop();
     11                 root->val = -root->val;
     12                 if (!root->left && !root->right && root->val == target) {
     13                     TreeNode *parent = um[root];
     14                     (parent->left == root ? parent->left : parent->right) = nullptr;
     15                 }
     16                 continue;
     17             }
     18             root->val = -root->val;
     19             if (root->left) {
     20                 um[root->left] = root;
     21                 st.push(root->left);
     22             }
     23             if (root->right) {
     24                 um[root->right] = root;
     25                 st.push(root->right);
     26             }
     27         }
     28         return dummy.left;
     29     }
     30 };