Mind palace

02-17

103. Binary Tree Zigzag Level Order Traversal

02-17

226. Invert Binary Tree

02-13

1008. Construct Binary Search Tree from Preorder Traversal

02-10

1120. Maximum Average Subtree

02-07

1110. Delete Nodes And Return Forest

01-25

666. Path Sum IV

01-20

101. Symmetric Tree

01-20

108. Convert Sorted Array to Binary Search Tree

01-19

145. Binary Tree Postorder Traversal

01-19

617. Merge Two Binary Trees