chlng 9

Challenges/2021/March-LeetCoding-Challenge.md

@@ -25,6 +25,7 @@ None
 |№|Title|Solution|Difficulty|
 | ----: | --- | --- | --- |
 |1332.|[Remove Palindromic Subsequences](https://leetcode.com/problems/remove-palindromic-subsequences/)|[Python](/Easy/1332.RemovePalindromicSubsequences.py)|Easy|
+|623.|[Add One Row to Tree](https://leetcode.com/problems/add-one-row-to-tree/)|[Python](/Medium/623.AddOneRowtoTree.py)|Medium|
 
 ## License
 The code is open-source and licensed under the [MIT License](/LICENSE).

Medium/623.AddOneRowtoTree.py

@@ -0,0 +1,111 @@
+'''
+    Given the root of a binary tree, then value v and depth 
+    d, you need to add a row of nodes with value v at the 
+    given depth d. The root node is at depth 1.
+
+    The adding rule is: given a positive integer depth d, 
+    for each NOT null tree nodes N in depth d-1, create two 
+    tree nodes with value v as N's left subtree root and 
+    right subtree root. And N's original left subtree should 
+    be the left subtree of the new left subtree root, its 
+    original right subtree should be the right subtree of 
+    the new right subtree root. If depth d is 1 that means 
+    there is no depth d-1 at all, then create a tree node 
+    with value v as the new root of the whole original tree, 
+    and the original tree is the new root's left subtree.
+
+    Example:
+    Input: 
+    A binary tree as following:
+            4
+          /   \
+         2     6
+        / \   / 
+       3   1 5
+    v = 1
+    d = 2
+
+    Output: 
+            4
+           / \
+          1   1
+         /     \
+        2       6
+       / \     / 
+      3   1   5   
+
+    Example:
+    Input: 
+    A binary tree as following:
+            4
+           /   
+          2    
+         / \   
+        3   1
+    v = 1
+    d = 3
+
+    Output: 
+            4
+           /   
+          2
+         / \    
+        1   1
+       /     \  
+      3       1
+
+    Note:
+        1. The given d is in range [1, maximum depth of the 
+           given tree + 1].
+        2. The given binary tree has at least one tree node.
+'''
+#Difficulty: Medium
+#109 / 109 test cases passed.
+#Runtime: 56 ms
+#Memory Usage: 16.2 MB
+
+#Runtime: 56 ms, faster than 64.46% of Python3 online submissions for Add One Row to Tree.
+#Memory Usage: 16.2 MB, less than 79.05% of Python3 online submissions for Add One Row to Tree.
+
+# Definition for a binary tree node.
+# class TreeNode:
+#     def __init__(self, val=0, left=None, right=None):
+#         self.val = val
+#         self.left = left
+#         self.right = right
+
+class Solution:
+    def addOneRow(self, root: TreeNode, v: int, d: int) -> TreeNode:
+        depth = 1
+        queue = [root]
+
+        if depth == d:
+            left = root
+            root = TreeNode(v)
+            root.left = left
+
+        while queue or depth <= d:
+            length = len(queue)
+            depth += 1
+            while length:
+                length -= 1
+                node = queue.pop(0)
+                if node:
+                    queue.append(node.left)
+                    queue.append(node.right)
+                if depth == d and node:
+                    left = node.left
+                    right = node.right
+                    if left:
+                        node.left = TreeNode(v)
+                        node.left.left = left
+                    if right:
+                        node.right = TreeNode(v)
+                        node.right.right = right
+                    if not node.left:
+                        node.left = TreeNode(v)
+                    if not node.right:
+                        node.right = TreeNode(v)
+                else:
+                    node = TreeNode(v)
+        return root

README.md

@@ -1,6 +1,6 @@
 # Python solutions of LeetCode problems.
 ![Language](https://img.shields.io/badge/language-Python-blue.svg) 
-![Problems Solved](https://img.shields.io/badge/problems%20solved-518%2F1618-orange) 
+![Problems Solved](https://img.shields.io/badge/problems%20solved-519%2F1618-orange) 
 [![License](https://img.shields.io/badge/license-MIT-green.svg)](./LICENSE) 
 ![Update](https://img.shields.io/badge/update-Daily-brightgreen.svg) 
 <br><br>
@@ -21,7 +21,7 @@ In this repository provided my Python solutions of LeetCode problems.
 2021:
 - [January LeetCoding Challenge](/Challenges/2021/January-LeetCoding-Challenge.md) - 27/31
 - [February LeetCoding Challenge](/Challenges/2021/February-LeetCoding-Challenge.md) - 23/28
-- [March LeetCoding Challenge](/Challenges/2021/March-LeetCoding-Challenge.md) - 8/31
+- [March LeetCoding Challenge](/Challenges/2021/March-LeetCoding-Challenge.md) - 9/31
 <br><br>
 ## Solutions
 *P.S. If you like this, please leave me a star.* ★
@@ -275,7 +275,8 @@ In this repository provided my Python solutions of LeetCode problems.
 |599.|[Minimum Index Sum of Two Lists](https://leetcode.com/problems/minimum-index-sum-of-two-lists/)|[Python](/Easy/599.MinimumIndexSumofTwoLists.py)|Easy|`Dictionary`, `enumerate`|
 |605.|[Can Place Flowers](https://leetcode.com/problems/can-place-flowers/)|[Python](/Easy/605.CanPlaceFlowers.py)|Easy|simple counter|
 |609.|[Find Duplicate File in System](https://leetcode.com/problems/find-duplicate-file-in-system/)|[Python](/Medium/609.FindDuplicateFileinSystem.py)|Medium|`Dictionary`, nested `for loop`, `list comprehension`|
-|622.|[Design Circular Queue](https://leetcode.com/problems/design-circular-queue/)|[Python](https://github.com/YuriSpiridonov/LeetCode/blob/master/Medium/622.DesignCircularQueue.py)|Medium|Implement through `list` (first time)|
+|622.|[Design Circular Queue](https://leetcode.com/problems/design-circular-queue/)|[Python](/Medium/622.DesignCircularQueue.py)|Medium|Implement through `list` (first time)|
+|623.|[Add One Row to Tree](https://leetcode.com/problems/add-one-row-to-tree/)|[Python](/Medium/623.AddOneRowtoTree.py)|Medium|`BFS`|
 |637.|[Average of Levels in Binary Tree](https://leetcode.com/problems/average-of-levels-in-binary-tree/)|[Python](/Easy/637.AverageofLevelsinBinaryTree.py)|Easy|`Binary Tree`, `Recursion`|
 |641.|[Design Circular Deque](https://leetcode.com/problems/design-circular-deque/)|[Python](/Medium/641.DesignCircularDeque.py)|Medium|Need to resolve without use of builtin functions (first time)|
 |645.|[Set Mismatch](https://leetcode.com/problems/set-mismatch/)|[Python](/Easy/645.SetMismatch.py)|Easy|`collections.Counter`|