# Binary Trees

## Types of techniques:

1. Depth First Search
   1. [pre-order-traversal](https://chkrishnatej.gitbook.io/interview-prep/trees/depth-first-search-dfs/pre-order-traversal "mention")
   2. [inorder-traversal](https://chkrishnatej.gitbook.io/interview-prep/trees/depth-first-search-dfs/inorder-traversal "mention")
   3. [post-order-traversal](https://chkrishnatej.gitbook.io/interview-prep/trees/depth-first-search-dfs/post-order-traversal "mention")
2. Height of the tree
3. Maximum Width/ Diamater of tree
   1. Handling binary tree problems with imaginary node by indexing 
   2. Counting Nodes
4. Lowest Common Ancestor (LCA)
5. Path Sum
6. Children Sum Property
7. Breadth First Search
   1. [breadth-first-search-bfs](https://chkrishnatej.gitbook.io/interview-prep/trees/breadth-first-search-bfs "mention")
   2. [left-side-view](https://chkrishnatej.gitbook.io/interview-prep/trees/binary-trees/binary-tree-views/left-side-view "mention")
   3. [right-side-view](https://chkrishnatej.gitbook.io/interview-prep/trees/binary-trees/binary-tree-views/right-side-view "mention")
   4. BFS with parent node
      1. Nodes at Distance K
      2. Time taken to infect
8. [boundary-view](https://chkrishnatej.gitbook.io/interview-prep/trees/binary-trees/binary-tree-views/boundary-view "mention")
9. Vertical Order Traversal
   1. [top-view](https://chkrishnatej.gitbook.io/interview-prep/trees/binary-trees/binary-tree-views/top-view "mention")
   2. [bottom-view](https://chkrishnatej.gitbook.io/interview-prep/trees/binary-trees/binary-tree-views/bottom-view "mention")
10. Symmetrics / Mirror Like Binary Trees
11. Constructing Unique Binary Tree
    1. [construct-binary-tree-based-on-inorder-and-preorder](https://chkrishnatej.gitbook.io/interview-prep/trees/binary-trees/construct-binary-tree-based-on-inorder-and-preorder "mention")
    2. [construct-binary-tree-based-on-inorder-and-postorder](https://chkrishnatej.gitbook.io/interview-prep/trees/binary-trees/construct-binary-tree-based-on-inorder-and-postorder "mention")
    3. <mark style="background-color:orange;">**NOTE:**</mark> <mark style="background-color:orange;"></mark><mark style="background-color:orange;">Cannot construct BT based on only preorder and postorder</mark>

## Bookmarks

* <https://leetcode.com/discuss/general-discussion/937307/iterative-recursive-dfs-bfs-tree-traversal-in-pre-post-levelorder-views>