# Python-LeetCode 581 Problem List

以下列出在Python-LeetCode 581系列筆記中，所用來示範說明的LeetCode Problem。並不包含用來舉例說明原理的非LeetCode問題。

Topics (Easy+Medium+Hard = subtotal)

* 第一招 搜尋：有序、無序與爬行 (1+0+0=1)
* [(題目連結) 1. Two Sum (Easy)](https://leetcode.com/problems/two-sum/)
* 第二招 Sliding Window (0+2+1=3)
* [(題目連結)3. Longest Substring Without Repeating Characters (Medium)](https://leetcode.com/problems/longest-substring-without-repeating-characters/)
* [(題目連結)1456. Maximum Number of Vowels in a Substring of Given Length (Medium)](https://leetcode.com/problems/maximum-number-of-vowels-in-a-substring-of-given-length/)
* [(題目連結) 30. Substring with Concatenation of All Words (Hard)](https://leetcode.com/problems/substring-with-concatenation-of-all-words/description/)。
* 第三招 Grid Traversal (0+3+1=4)
* [(題目連結) 1162. As Far from Land as Possible (Medium)](https://leetcode.com/problems/as-far-from-land-as-possible/)
* [(題目連結) 695. Max Area of Island (Medium)](https://leetcode.com/problems/max-area-of-island/description/)
* [(題目連結) 1559. Detect Cycles in 2D Grid (Medium)](https://leetcode.com/problems/detect-cycles-in-2d-grid/description/)
* [(題目連結) 1293. Shortest Path in a Grid with Obstacles Elimination (Hard)](https://leetcode.com/problems/shortest-path-in-a-grid-with-obstacles-elimination/)
* 第四招 前綴和 Prefix Sum (1+4+3=8)
* [(題目連結) 303. Range Sum Query - Immutable (Easy)](https://leetcode.com/problems/range-sum-query-immutable/description/)
* [(題目連結) 304. Range Sum Query 2D - Immutable (Medium)](https://leetcode.com/problems/range-sum-query-2d-immutable/description/)
* [(題目連結) 2017. Grid Game (Medium)](https://leetcode.com/problems/grid-game/description/)
* [(題目連結) 560. Subarray Sum Equals K (Medium)](https://leetcode.com/problems/subarray-sum-equals-k/description/)
* [(題目連結) 523. Continuous Subarray Sum (Medium)](https://leetcode.com/problems/continuous-subarray-sum/)
* [(題目連結) 1074. Number of Submatrices That Sum to Target (Hard)](https://leetcode.com/problems/number-of-submatrices-that-sum-to-target/)
* [(題目連結) 239. Sliding Window Maximum (Hard)](https://leetcode.com/problems/sliding-window-maximum/)
* [(題目連結) 862. Shortest Subarray with Sum at Least K (Hard)](https://leetcode.com/problems/shortest-subarray-with-sum-at-least-k/)
* 第五招 優先佇列 Priority Queue/Heap (0+2+3=5)
* [(題目連結) 23. Merge k Sorted Lists (Hard)](https://leetcode.com/problems/merge-k-sorted-lists/description/)
* [(題目連結) 1942. The Number of the Smallest Unoccupied Chair (Medium)](https://leetcode.com/problems/the-number-of-the-smallest-unoccupied-chair/description/)
* [(題目連結) 239. Sliding Window Maximum (Hard)](https://leetcode.com/problems/sliding-window-maximum/)
* [(題目連結) 295. Find Median from Data Stream (hard)](https://leetcode.com/problems/find-median-from-data-stream/)
* [(題目連結)1353. Maximum Number of Events That Can Be Attended (Medium)](https://leetcode.com/problems/maximum-number-of-events-that-can-be-attended/)
* 第六招 Counter (1+7+1=9)
* [(題目連結) 347. Top K Frequent Elements (Medium)](https://leetcode.com/problems/top-k-frequent-elements/)
* [(題目連結) 692. Top K Frequent Words (Medium)](https://leetcode.com/problems/top-k-frequent-words/)
* [(題目連結)1128. Number of Equivalent Domino Pairs (Easy)](https://leetcode.com/problems/number-of-equivalent-domino-pairs/)
* [(題目連結) 299. Bulls and Cows (Medium)](https://leetcode.com/problems/bulls-and-cows/)
* [(題目連結)1347. Minimum Number of Steps to Make Two Strings Anagram (Medium)](https://leetcode.com/problems/minimum-number-of-steps-to-make-two-strings-anagram/)
* [(題目連結) 1400. Construct K Palindrome Strings (Medium)](https://leetcode.com/problems/construct-k-palindrome-strings/)
* [(題目連結) 1419. Minimum Number of Frogs Croaking (Medium)](https://leetcode.com/problems/minimum-number-of-frogs-croaking/)
* [(題目連結) 992. Subarrays with K Different Integers (hard)](https://leetcode.com/problems/subarrays-with-k-different-integers/)
* [(題目連結)1519. Number of Nodes in the Sub-Tree With the Same Label (Medium)](https://leetcode.com/problems/number-of-nodes-in-the-sub-tree-with-the-same-label/)
* 第七招 Math (1+10+3=14)
* [(題目連結) 204. Count Primes (Medium)](https://leetcode.com/problems/count-primes/)
* [(題目連結) 650. 2 Keys Keyboard (Medium)](https://leetcode.com/problems/fraction-addition-and-subtraction/description/)
* [(題目連結) 2521. Distinct Prime Factors of Product of Array (Medium)](https://leetcode.com/problems/distinct-prime-factors-of-product-of-array/)
* [(題目連結) 263. Ugly Number (Easy)](https://leetcode.com/problems/ugly-number/)
* [(題目連結) 264. Ugly Number II (Medium)](https://leetcode.com/problems/ugly-number-ii/)
* [(題目連結) 313. Super Ugly Number (Medium)](https://leetcode.com/problems/super-ugly-number/)
* [(題目連結) 2447. Number of Subarrays With GCD Equal to K (Medium)](https://leetcode.com/problems/number-of-subarrays-with-gcd-equal-to-k/description/)
* [(題目連結) 592. Fraction Addition and Subtraction (Medium)](https://leetcode.com/problems/fraction-addition-and-subtraction/description/)
* [(題目連結) 1201. Ugly Number III (Medium)](https://leetcode.com/problems/ugly-number-iii/)
* [(題目連結) 60. Permutation Sequence (Hard)](https://leetcode.com/problems/permutation-sequence/)
* [(題目連結) 1012. Numbers With Repeated Digits (Hard)](https://leetcode.com/problems/numbers-with-repeated-digits/)
* [(題目連結) 1015. Smallest Integer Divisible by K (Medium)](https://leetcode.com/problems/smallest-integer-divisible-by-k/)
* [(題目連結) 1916. Count Ways to Build Rooms in an Ant Colony (Hard)](https://leetcode.com/problems/count-ways-to-build-rooms-in-an-ant-colony/)
* [(題目連結) 1922. Count Good Numbers (Medium)](https://leetcode.com/problems/count-good-numbers/)
* 第八招 Sorting (1+18+2=21)
* [(題目連結) 912. Sort an Array (Medium)](https://leetcode.com/problems/sort-an-array/)
* [(題目連結) 147. Insertion Sort List (Medium)](https://leetcode.com/problems/insertion-sort-list/)
* [(題目連結) 905. Sort Array By Parity (Easy)](https://leetcode.com/problems/sort-array-by-parity/)
* [(題目連結) 1329. Sort the Matrix Diagonally (Medium)](https://leetcode.com/problems/sort-the-matrix-diagonally/)
* [(題目連結) 475. Heaters (Medium)](https://leetcode.com/problems/heaters/)
* [(題目連結) 49. Group Anagrams (Medium)](https://leetcode.com/problems/group-anagrams/description/)
* [(題目連結) 451. Sort Characters By Frequency (Medium)](https://leetcode.com/problems/sort-characters-by-frequency/)
* [(題目連結) 869. Reordered Power of 2 (Medium)](https://leetcode.com/problems/reordered-power-of-2/)
* [(題目連結) 973. K Closest Points to Origin (Medium)](https://leetcode.com/problems/k-closest-points-to-origin/)
* [(題目連結) 56. Merge Intervals (Medium)](https://leetcode.com/problems/merge-intervals/)
* [(題目連結) 435. Non-overlapping Intervals (Medium)](https://leetcode.com/problems/non-overlapping-intervals/)
* [(題目連結) 1090. Largest Values From Labels (Medium)](https://leetcode.com/problems/largest-values-from-labels/)
* [(題目連結) 1296. Divide Array in Sets of K Consecutive Numbers (Medium)](https://leetcode.com/problems/divide-array-in-sets-of-k-consecutive-numbers/)
* [(題目連結) 1921. Eliminate Maximum Number of Monsters (Medium)](https://leetcode.com/problems/eliminate-maximum-number-of-monsters/)
* [(題目連結) 179. Largest Number (Medium)](https://leetcode.com/problems/largest-number/)
* [(題目連結) 791. Custom Sort String (Medium)](https://leetcode.com/problems/custom-sort-string/)
* [(題目連結) 581. Shortest Unsorted Continuous Subarray (Medium)](https://leetcode.com/problems/shortest-unsorted-continuous-subarray/)
* [(題目連結) 220. Contains Duplicate III (Hard)](https://leetcode.com/problems/contains-duplicate-iii/description/)
* [(題目連結) 969. Pancake Sorting (Medium)](https://leetcode.com/problems/pancake-sorting/)
* [(題目連結) 1383. Maximum Performance of a Team (Hard)](https://leetcode.com/problems/maximum-performance-of-a-team/)
* [(題目連結) 2007. Find Original Array From Doubled Array (Medium)](https://leetcode.com/problems/find-original-array-from-doubled-array/)
* 第九招 Greedy algorithm (1+12+11=24)
* [(題目連結) 455. Assign Cookies (Easy)](https://leetcode.com/problems/assign-cookies/description/)
* [(題目連結) 2405. Optimal Partition of String (Medium)](https://leetcode.com/problems/optimal-partition-of-string/)
* [(題目連結) 122. Best Time to Buy and Sell Stock II (Medium)](https://leetcode.com/problems/best-time-to-buy-and-sell-stock-ii/)
* [(題目連結) 55. Jump Game (Medium)](https://leetcode.com/problems/jump-game/)
* [(題目連結) 45. Jump Game II (Medium)](https://leetcode.com/problems/jump-game-ii/)
* [(題目連結) 2366. Minimum Replacements to Sort the Array (Hard)](https://leetcode.com/problems/minimum-replacements-to-sort-the-array/)
* [(題目連結) 765. Couples Holding Hands (Hard)](https://leetcode.com/problems/couples-holding-hands/)
* [(題目連結)881. Boats to Save People (Medium)](https://leetcode.com/problems/boats-to-save-people/)
* [(題目連結) 910. Smallest Range II (Medium)](https://leetcode.com/problems/smallest-range-ii/)
* [(題目連結) 1029. Two City Scheduling (Medium)](https://leetcode.com/problems/two-city-scheduling/)
* [(題目連結) 452. Minimum Number of Arrows to Burst Balloons (Medium)](https://leetcode.com/problems/minimum-number-of-arrows-to-burst-balloons/)
* [(題目連結) 135. Candy (Hard)](https://leetcode.com/problems/candy/description/)
* [(題目連結) 757. Set Intersection Size At Least Two (Hard)](https://leetcode.com/problems/set-intersection-size-at-least-two/)
* [(題目連結) 632. Smallest Range Covering Elements from K Lists (Hard)](https://leetcode.com/problems/smallest-range-covering-elements-from-k-lists/)
* [(題目連結) 630. Course Schedule III (Hard)](https://leetcode.com/problems/course-schedule-iii/)
* [(題目連結) 871. Minimum Number of Refueling Stops (Hard)](https://leetcode.com/problems/minimum-number-of-refueling-stops/)
* [(題目連結) 1606. Find Servers That Handled Most Number of Requests (Hard)](https://leetcode.com/problems/find-servers-that-handled-most-number-of-requests/)
* [(題目連結) 410. Split Array Largest Sum (Hard)](https://leetcode.com/problems/split-array-largest-sum/)
* [(題目連結) 1802. Maximum Value at a Given Index in a Bounded Array (Medium)](https://leetcode.com/problems/maximum-value-at-a-given-index-in-a-bounded-array/)
* [(題目連結) 2616. Minimize the Maximum Difference of Pairs (Medium)](https://leetcode.com/problems/minimize-the-maximum-difference-of-pairs/)
* [(題目連結) 11. Container With Most Water (Medium)](https://leetcode.com/problems/container-with-most-water/)
* [(題目連結) 321. Create Maximum Number (Hard)](https://leetcode.com/problems/create-maximum-number/description/)
* [(題目連結) 517. Super Washing Machines (Hard)](https://leetcode.com/problems/super-washing-machines/)
* [(題目連結) 316. Remove Duplicate Letters (Medium)](https://leetcode.com/problems/remove-duplicate-letters/description/)
* 第10招 單調隊列 Monotonic stack and deque (1+6+7=14)
* [(題目連結)496. Next Greater Element I (Easy)](https://leetcode.com/problems/next-greater-element-i/)
* [(題目連結)239. Sliding Window Maximum (hard)](https://leetcode.com/problems/sliding-window-maximum/)
* [(題目連結) 907. Sum of Subarray Minimums (Medium)](https://leetcode.com/problems/sum-of-subarray-minimums/)
* [(題目連結) 84. Largest Rectangle in Histogram (Hard)](https://leetcode.com/problems/largest-rectangle-in-histogram/)
* [(題目連結) 85. Maximal Rectangle (Hard)](https://leetcode.com/problems/maximal-rectangle/)
* [(題目連結) 1944. Number of Visible People in a Queue (Hard)](https://leetcode.com/problems/number-of-visible-people-in-a-queue/)
* [(題目連結) 1776. Car Fleet II (Hard)](https://leetcode.com/problems/car-fleet-ii/)
* [(題目連結) 1856. Maximum Subarray Min-Product (Medium)](https://leetcode.com/problems/maximum-subarray-min-product/)
* [(題目連結) 1130. Minimum Cost Tree From Leaf Values (Medium)](https://leetcode.com/problems/minimum-cost-tree-from-leaf-values/)
* [(題目連結) 654. Maximum Binary Tree (Medium)](https://leetcode.com/problems/maximum-binary-tree/)
* [(題目連結) 1499. Max Value of Equation (Hard)](https://leetcode.com/problems/max-value-of-equation/)
* [(題目連結) 1438. Longest Continuous Subarray With Absolute Diff Less Than or Equal to Limit (Medium)](https://leetcode.com/problems/longest-continuous-subarray-with-absolute-diff-less-than-or-equal-to-limit/)
* [(題目連結) 1425. Constrained Subsequence Sum (Hard)](https://leetcode.com/problems/constrained-subsequence-sum/)
* [(題目連結) 1696. Jump Game VI (Medium)](https://leetcode.com/problems/jump-game-vi/)
* 第11招 Graph Traversal (1+9+12=22)
* [(題目連結)102. Binary Tree Level Order Traversal (Medium)](https://leetcode.com/problems/binary-tree-level-order-traversal/)
* [(題目連結)1161. Maximum Level Sum of a Binary Tree (Medium)](https://leetcode.com/problems/maximum-level-sum-of-a-binary-tree/)
* [(題目連結)297. Serialize and Deserialize Binary Tree (Hard)](https://leetcode.com/problems/serialize-and-deserialize-binary-tree/)
* [(題目連結)1123. Lowest Common Ancestor of Deepest Leaves (Medium)](https://leetcode.com/problems/lowest-common-ancestor-of-deepest-leaves/description/)
* [(題目連結) 130. Surrounded Regions (Medium)](https://leetcode.com/problems/surrounded-regions/)
* [(題目連結) 200. Number of Islands (Medium)](https://leetcode.com/problems/number-of-islands/)
* [(題目連結) 417. Pacific Atlantic Water Flow (Medium)](https://leetcode.com/problems/pacific-atlantic-water-flow/)
* [(題目連結) 675. Cut Off Trees for Golf Event (Hard)](https://leetcode.com/problems/cut-off-trees-for-golf-event/description/)
* [(題目連結) 749. Contain Virus (Hard)](https://leetcode.com/problems/contain-virus/)
* [(題目連結) 785. Is Graph Bipartite? (Medium)](https://leetcode.com/problems/is-graph-bipartite/)
* [(題目連結) 815. Bus Routes (Hard)](https://leetcode.com/problems/bus-routes/)
* [(題目連結) 924. Minimize Malware Spread (Hard)](https://leetcode.com/problems/minimize-malware-spread/)
* [(題目連結) 1129. Shortest Path with Alternating Colors (Medium)](https://leetcode.com/problems/shortest-path-with-alternating-colors/)
* [(題目連結) 127. Word Ladder (Hard)](https://leetcode.com/problems/word-ladder/)
* [(題目連結) 126. Word Ladder II (Hard)](https://leetcode.com/problems/word-ladder-ii/)
* [(題目連結) 773. Sliding Puzzle (Hard)](https://leetcode.com/problems/sliding-puzzle/)
* [(題目連結) 207. Course Schedule (Medium)](https://leetcode.com/problems/course-schedule/)
* [(題目連結) 210. Course Schedule II (Easy)](https://leetcode.com/problems/course-schedule-ii/)
* [(題目連結) 1203. Sort Items by Groups Respecting Dependencies (Hard)](https://leetcode.com/problems/sort-items-by-groups-respecting-dependencies/)
* [(題目連結) 1298. Maximum Candies You Can Get from Boxes (Hard)](https://leetcode.com/problems/maximum-candies-you-can-get-from-boxes/)
* [(題目連結) 1857. Largest Color Value in a Directed Graph (Hard)](https://leetcode.com/problems/largest-color-value-in-a-directed-graph/)
* [(題目連結) 2050. Parallel Courses III (Hard)](https://leetcode.com/problems/parallel-courses-iii/description/)
* 第12招 Shortest Path (0+3+3=6)
* [(題目連結) 743. Network Delay Time (Medium)](https://leetcode.com/problems/network-delay-time/)
* [(題目連結) 787. Cheapest Flights Within K Stops (Medium)](https://leetcode.com/problems/cheapest-flights-within-k-stops/)
* [(題目連結) 882. Reachable Nodes In Subdivided Graph (Hard)](https://leetcode.com/problems/reachable-nodes-in-subdivided-graph/)
* [(題目連結) 1976. Number of Ways to Arrive at Destination (Medium)](https://leetcode.com/problems/number-of-ways-to-arrive-at-destination/)
* [(題目連結) 2045. Second Minimum Time to Reach Destination (Hard)](https://leetcode.com/problems/second-minimum-time-to-reach-destination/description/)
* [(題目連結) 2203. Minimum Weighted Subgraph With the Required Paths (Hard)](https://leetcode.com/problems/minimum-weighted-subgraph-with-the-required-paths/)
* 第13招 Union-and-Find and Minimum spanning tree (0+4+7=11)
* [(題目連結) 684. Redundant Connection (Medium)](https://leetcode.com/problems/redundant-connection/)
* [(題目連結) 128. Longest Consecutive Sequence (Medium)](https://leetcode.com/problems/longest-consecutive-sequence/description/)
* [(題目連結) 200. Number of Islands (Medium)](https://leetcode.com/problems/number-of-islands/description/)
* [(題目連結) 803. Bricks Falling When Hit (Hard)](https://leetcode.com/problems/bricks-falling-when-hit/)
* [(題目連結) 827. Making A Large Island (Hard)](https://leetcode.com/problems/making-a-large-island/)
* [(題目連結) 952. Largest Component Size by Common Factor (Hard)](https://leetcode.com/problems/largest-component-size-by-common-factor/)
* [(題目連結) 1627. Graph Connectivity With Threshold (Hard)](https://leetcode.com/problems/graph-connectivity-with-threshold/)
* [(題目連結) 1697. Checking Existence of Edge Length Limited Paths (Hard)](https://leetcode.com/problems/checking-existence-of-edge-length-limited-paths/)
* [(題目連結) 1970. Last Day Where You Can Still Cross (Hard)](https://leetcode.com/problems/last-day-where-you-can-still-cross/)
* [(題目連結) 1584. Min Cost to Connect All Points (Medium)](https://leetcode.com/problems/min-cost-to-connect-all-points/)
* [(題目連結) 1489. Find Critical and Pseudo-Critical Edges in Minimum Spanning Tree (Hard)](https://leetcode.com/problems/find-critical-and-pseudo-critical-edges-in-minimum-spanning-tree/)
* 第14招 Dynamic Programming I： 基本原理與一維DP (2+9+4=15)
* [(題目連結) 70. Climbing Stairs (Easy)](https://leetcode.com/problems/climbing-stairs/)
* [(題目連結) 64. Minimum Path Sum (Medium)](https://leetcode.com/problems/minimum-path-sum/)
* [(題目連結) 53. Maximum Subarray (Medium)](https://leetcode.com/problems/maximum-subarray/)
* [(題目連結) 198. House Robber (Medium)](https://leetcode.com/problems/house-robber/)
* [(題目連結) 213. House Robber II (Medium)](https://leetcode.com/problems/house-robber-ii/)
* [(題目連結) 337. House Robber III (Medium)](https://leetcode.com/problems/house-robber-iii/)
* [(題目連結) 121. Best Time to Buy and Sell Stock (Easy)](https://leetcode.com/problems/best-time-to-buy-and-sell-stock/)
* [(題目連結) 122. Best Time to Buy and Sell Stock II (Medium)](https://leetcode.com/problems/best-time-to-buy-and-sell-stock-ii/)
* [(題目連結) 123. Best Time to Buy and Sell Stock III (Hard)](https://leetcode.com/problems/best-time-to-buy-and-sell-stock-iii/)
* [(題目連結) 188. Best Time to Buy and Sell Stock IV (Hard)](https://leetcode.com/problems/best-time-to-buy-and-sell-stock-iv/)
* [(題目連結) 446. Arithmetic Slices II - Subsequence (Hard)](https://leetcode.com/problems/arithmetic-slices-ii-subsequence/)
* [(題目連結) 300. Longest Increasing Subsequence (Medium)](https://leetcode.com/problems/longest-increasing-subsequence/)
* [(題目連結) 673. Number of Longest Increasing Subsequence (Medium)](https://leetcode.com/problems/number-of-longest-increasing-subsequence/description/)
* [(題目連結) 898. Bitwise ORs of Subarrays (Medium)](https://leetcode.com/problems/bitwise-ors-of-subarrays/)
* [(題目連結) 1235. Maximum Profit in Job Scheduling (Hard)](https://leetcode.com/problems/maximum-profit-in-job-scheduling/)
* 第15招 Dynamic Programming II：二維 (0+8+6=14)
* [(題目連結) 63. Unique Paths II (Medium)](https://leetcode.com/problems/unique-paths-ii/)
* [(題目連結) 64. Minimum Path Sum (Medium)](https://leetcode.com/problems/minimum-path-sum/)
* [(題目連結) 2304. Minimum Path Cost in a Grid (Medium)](https://leetcode.com/problems/minimum-path-cost-in-a-grid/description/)
* [(題目連結) 322. Coin Change (Medium)](https://leetcode.com/problems/coin-change/description/)
* [(題目連結) 416. Partition Equal Subset Sum (Medium)](https://leetcode.com/problems/partition-equal-subset-sum/)
* [(題目連結) 2742. Painting the Walls (Hard)](https://leetcode.com/problems/painting-the-walls/)
* [(題目連結) 1143. Longest Common Subsequence (Medium)](https://leetcode.com/problems/longest-common-subsequence/)
* [(題目連結) 115. Distinct Subsequences (Hard)](https://leetcode.com/problems/distinct-subsequences/)
* [(題目連結) 221. Maximal Square (Medium)](https://leetcode.com/problems/maximal-square/)
* [(題目連結) 920. Number of Music Playlists (Hard)](https://leetcode.com/problems/number-of-music-playlists/)
* [(題目連結) 1547. Minimum Cost to Cut a Stick (Hard)](https://leetcode.com/problems/minimum-cost-to-cut-a-stick/description/)
* [(題目連結) 87. Scramble String (Hard)](https://leetcode.com/problems/scramble-string/description/)
* [(題目連結) 664. Strange Printer (Hard)](https://leetcode.com/problems/strange-printer/)
* [(題目連結) 241. Different Ways to Add Parentheses (Medium)](https://leetcode.com/problems/different-ways-to-add-parentheses/)
* 第16招 Dynamic Programming III： Tree and Subset (0+2+9=11)
* [(題目連結) 124. Binary Tree Maximum Path Sum (Hard)](https://leetcode.com/problems/binary-tree-maximum-path-sum/)
* [(題目連結) 310. Minimum Height Trees (Medium)](https://leetcode.com/problems/minimum-height-trees/description/)
* [(題目連結) 834. Sum of Distances in Tree (Hard)](https://leetcode.com/problems/sum-of-distances-in-tree/)
* [(題目連結) 968. Binary Tree Cameras (Hard)](https://leetcode.com/problems/binary-tree-cameras/description/)
* [(題目連結) 1349. Maximum Students Taking Exam (Hard)](https://leetcode.com/problems/maximum-students-taking-exam/)
* [(題目連結) 1125. Smallest Sufficient Team (Medium)](https://leetcode.com/problems/smallest-sufficient-team/description/)
* [(題目連結) 847. Shortest Path Visiting All Nodes (Hard)](https://leetcode.com/problems/shortest-path-visiting-all-nodes/)
* [(題目連結) 1434. Number of Ways to Wear Different Hats to Each Other (Hard)](https://leetcode.com/problems/number-of-ways-to-wear-different-hats-to-each-other/)
* [(題目連結) 691. Stickers to Spell Word (Hard)](https://leetcode.com/problems/stickers-to-spell-word/description/)
* [(題目連結) 1655. Distribute Repeating Integers (Hard)](https://leetcode.com/problems/distribute-repeating-integers/)
* [(題目連結) 698. Partition to K Equal Sum Subsets (Hard)](https://leetcode.com/problems/partition-to-k-equal-sum-subsets/)
* 第17招 String (I) (1+6+6=13)
* [(題目連結) 49. Group Anagrams (Medium)](https://leetcode.com/problems/group-anagrams/)
* [(題目連結) 1061. Lexicographically Smallest Equivalent String (Medium)](https://leetcode.com/problems/lexicographically-smallest-equivalent-string/)
* [(題目連結) 2391. Minimum Amount of Time to Collect Garbage (Medium)](https://leetcode.com/problems/minimum-amount-of-time-to-collect-garbage/)
* [(題目連結) 87. Scramble String (Hard)](https://leetcode.com/problems/scramble-string/)
* [(題目連結) 438. Find All Anagrams in a String (Medium)](https://leetcode.com/problems/find-all-anagrams-in-a-string/)
* [(題目連結) 472. Concatenated Words (Hard)](https://leetcode.com/problems/concatenated-words/description/)
* [(題目連結) 10. Regular Expression Matching (Hard)](https://leetcode.com/problems/regular-expression-matching/)
* [(題目連結) 65. Valid Number (Hard)](https://leetcode.com/problems/valid-number/)
* [(題目連結) 224. Basic Calculator (Hard)](https://leetcode.com/problems/basic-calculator/)
* [(題目連結) 28. Find the Index of the First Occurrence in a String (Easy)](https://leetcode.com/problems/find-the-index-of-the-first-occurrence-in-a-string/)
* [(題目連結) 1764. Form Array by Concatenating Subarrays of Another Array (Medium)](https://leetcode.com/problems/form-array-by-concatenating-subarrays-of-another-array/)
* [(題目連結) 1910. Remove All Occurrences of a Substring (Medium)](https://leetcode.com/problems/remove-all-occurrences-of-a-substring/)
* [(題目連結) 1392. Longest Happy Prefix (Hard)](https://leetcode.com/problems/longest-happy-prefix/)
* 第18招 String (II) (0+2+8=10)
* [(題目連結) 5. Longest Palindromic Substring (Medium)](https://leetcode.com/problems/longest-palindromic-substring/description/)
* [(題目連結) 1960. Maximum Product of the Length of Two Palindromic Substrings (Hard)](https://leetcode.com/problems/maximum-product-of-the-length-of-two-palindromic-substrings/)
* [(題目連結) 1745. Palindrome Partitioning IV (Hard)](https://leetcode.com/problems/palindrome-partitioning-iv/)
* [(題目連結) 1771. Maximize Palindrome Length From Subsequences (Hard)](https://leetcode.com/problems/maximize-palindrome-length-from-subsequences/)
* [(題目連結) 208. Implement Trie (Prefix Tree) (Medium)](https://leetcode.com/problems/find-the-index-of-the-first-occurrence-in-a-string/)
* [(題目連結) 745. Prefix and Suffix Search (Hard)](https://leetcode.com/problems/prefix-and-suffix-search/)
* [(題目連結) 1032. Stream of Characters (Hard)](https://leetcode.com/problems/stream-of-characters/)
* [(題目連結) 214. Shortest Palindrome (Hard)](https://leetcode.com/problems/shortest-palindrome/)
* [(題目連結) 1044. Longest Duplicate Substring (Hard)](https://leetcode.com/problems/longest-duplicate-substring/description/)
* [(題目連結) 1316. Distinct Echo Substrings (Hard)](https://leetcode.com/problems/distinct-echo-substrings/)
* 第19招 Branching algorithm and Backtracking (0+0+8=8)
* [(題目連結) 1601. Maximum Number of Achievable Transfer Requests (Hard)](https://leetcode.com/problems/maximum-number-of-achievable-transfer-requests/)
* [(題目連結) 1723. Find Minimum Time to Finish All Jobs (Hard)](https://leetcode.com/problems/find-minimum-time-to-finish-all-jobs/)
* [(題目連結) 473. Matchsticks to Square (Hard)](https://leetcode.com/problems/matchsticks-to-square/)
* [(題目連結) 140. Word Break II (Hard)](https://leetcode.com/problems/word-break-ii/)
* [(題目連結) 301. Remove Invalid Parentheses (Hard)](https://leetcode.com/problems/remove-invalid-parentheses/)
* [(題目連結) 1681. Minimum Incompatibility (Hard)](https://leetcode.com/problems/minimum-incompatibility/description/)
* [(題目連結) 2305. Fair Distribution of Cookies (Hard)](https://leetcode.com/problems/fair-distribution-of-cookies/)
* [(題目連結) 1655. Distribute Repeating Integers (Hard)](https://leetcode.com/problems/distribute-repeating-integers/)

Total number of problems: 11+107+95=213