Leetcode # 101. Symmetric Tree
https://leetcode.com/problems/symmetric-tree/ Solution Time Complexity: O(len(tree)) Space Complexity: O(len(tree)) (The input and output generally do not count towards the space complexity.) class So ...
Leetcode # 112. Path Sum
- 2022.12.09
- Depth-First Search LeetCode Tree
https://leetcode.com/problems/path-sum/ Solution Return True if the tree has a root-to-leaf path Time Complexity: O(len(tree)) Space Complexity: O(len(tree)) (The input and output generally do not cou ...
Leetcode # 323. Number of Connected Components in an Undirected Graph
- 2022.12.09
- Disjoint Set Union LeetCode
https://leetcode.com/problems/number-of-connected-components-in-an-undirected-graph Solution: Disjoint Set Union (DSU) Time Complexity: O() Space Complexity: O() (The input and output generally do not ...
Leetcode # 200. Number of Islands
- 2022.12.09
- Disjoint Set Union LeetCode
https://leetcode.com/problems/number-of-islands/ Solution: Disjoint Set Union (DSU) Time Complexity: O(len(grid) * len(grid[0])) Space Complexity: O(len(grid) * len(grid[0])) (The input and output gen ...
Leetcode # 872. Leaf-Similar Trees
- 2022.12.08
- Depth-First Search Python Tree
https://leetcode.com/problems/leaf-similar-trees/ Solution Time Complexity: O(len(tree1 + tree2)) Space Complexity: O(len(tree1 + tree2)) (The input and output generally do not count towards the space ...
[Python] Assignment Expressions 「:=」
- 2022.12.08
- Assignment Expressions Python
NAME := expr Assign to variables within an expression using the notation. 使用例 if Statement sex = 0 if sex == 0: print("boy") ⇒ if (sex := 0) == 0: print("boy") while Statement 例１：讀取檔案 file = open("... ...
[Python] 判斷是否為 空(None) (0 為 False)
Conditionals / Conditional expressions a is None / a is not None a == None / a != None not a (not 0 為 True) Python 中視作 False 的物件 None, False 0 (), [], {}, set(), range(0) In if/while statement if a: ...
Leetcode # 98. Validate Binary Search Tree
- 2022.12.08
- ★★ Medium Depth-First Search LeetCode Tree
https://leetcode.com/problems/validate-binary-search-tree/ Solution Time Complexity: O(len(BST)) Space Complexity: O(len(BST)) (The input and output generally do not count towards the space complexity ...
Leetcode # 20. Valid Parentheses
- 2022.12.08
- LeetCode Parentheses Parsing Stack
https://leetcode.com/problems/valid-parentheses/ Solution Time Complexity: O(len(s)) Space Complexity: O(len(s)) (The input and output generally do not count towards the space complexity.) class Solut ...
Leetcode # 938. Range Sum of BST
- 2022.12.08
- Breadth-First Search LeetCode
https://leetcode.com/problems/range-sum-of-bst/ Solution Time Complexity: O(len(tree)) Space Complexity: O(len(tree)) (The input and output generally do not count towards the space complexity.) class ...
