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Floating-Point Error

ε Epsilon Python float_info.epsilon 2.220446049250313e-16 #FloatingPointError

https://leetcode.com/problems/buddy-strings Solution 交換兩個 character 後 s 和 gaol 會一樣 ⇒ 回傳 True s 和 goal 只有在 i, j 的兩個 character 不一樣 (s[i] != goal[i] and s[j] != goal [j])，且 s[i] = goal[j], s[j] = goal[i ...

Leetcode # 50. Pow(x, n)

2023.07.24
LeetCode Mathematics Memoization

https://leetcode.com/problems/powx-n Solution (Memoization) Time Complexity: O(log(n)) Space Complexity: O(log(n)) (The input and output generally do not count towards the space complexity.) class Sol ...

Leetcode # 67. Add Binary

2023.07.24
Big Number LeetCode

https://leetcode.com/problems/add-binary Solution Time Complexity: O(max(len(a), len(b)) Space Complexity: O(1) (The input and output generally do not count towards the space complexity.) class Soluti ...

Big Number 大數運算

2023.07.24
Big Number Mathematics

Lowest Common Ancestor

2023.07.23
Binary Lifting Data Structure Lowest Common Ancestor Tree

The lowest common ancestor (LCA) (also called least common ancestor) of two nodes u and v in a tree or directed acyclic graph (DAG) T is the lowest (i.e. deepest) node that has both v and w as descend ...

Leetcode # 2786. Visit Array Positions to Maximize Score

2023.07.23
★★ Medium Dynamic Programming LeetCode Optimized Space Complexity

https://leetcode.com/contest/biweekly-contest-109/problems/visit-array-positions-to-maximize-score/ Solution Time Complexity: O(len(nums)) Space Complexity: O(1) (The input and output generally do not ...

Leetcode # 6922. Ways to Express an Integer as Sum of Powers

https://leetcode.com/contest/biweekly-contest-109/problems/ways-to-express-an-integer-as-sum-of-powers/ Solution 當你需要的是出現的次數而無關順序時 ⇒ 使用 list Counter Time Complexity: O() Space Complexity: O() (The inp ...

[Python] count()

2023.07.23
Python

計算value出現的次數 list.count(value) string.count(value, start, end)

Parsing

2023.07.22
Algorithm Binary Tree Parsing Stack

Traversal 遍歷 (Using Binary Tree) 請參考：Binary Tree 二元樹 – Traversal 遍歷範例 Leetcode # 439. Ternary Expression Parser Using Stack 一般來說，優先度相同時，優先順序從左至右而當優先順序從右至左時，要改為逆序存取（範例：Leetcode # 439. Ternary ...