leetcode-python

DFS/BFS, backtracing, DP

• Easy
  

53 MaximumSubArray, 70 Climb Stairs

• Medium
  

36 Valid Sudoku
55 Jump Game, 45 JumpGame II
62 Unique Paths, 63 UniquePaths II, 64 MinimumPathSum
322 CoinChange 79 Word Search, 127 WordLadder, 200 NumberOfIslands
89 Gray Code
91 Decode ways, 93 Restore IP Addrs 931 minFallingPathSum, 718 MaximumLenOfRepeatedSubArr, 1048 LongestStrChain

• Hard

10 regularExpMatching, 44 Wildcard Matching
37 Sudoku Solver, 51 N-Queens, 52 N-Queens II
72 Edit Distance
84 Largest Rectangle in Histogram, 85 Maximal Rectangle
87 Scramble String, 97 Interleaving string, 115 DistinctSubsequences, 120 Triangle

• Combination and Permutations

17 LetterCombinationOfAPhoneNumber, 39 CombinationSum, 40 CombinationSum II, 77 Combinations, 78 Subsets, 90 Subsets II
46 Permutations, 47 Permutations II, 60 Permutation Sequence

String

• Easy

14 LongestCommonPrefix, 28 Implement strStr(), 387 FirstUniqueCharacterInAString
443 StringCompression, 720 LongestWordInDict, 1422 MaximumScoreAfterSplittingAString

• Medium

8 StrintToInteger atoi, 151 ReverseWordsInAString, 166 FractionToRecurringDecimal

• Hard

273 IntToEnglishWords

Array

• Easy

26 RemoveDupFromSortedArray, 27 RemoveElement, 66 PlusOne, 67 AddBinary
88 Merge Sorted Array, 169 MajorityElement, 189 RotateArr, 268 MissingNumber
118 Pascal's Triangle, 119 Pascal's Triangle II
349 IntersectionOf2Arrays, 628 maximumProductOf3Nums, 1010 numPairsDivisibleBy60

• Medium

238 ProductOfArrExceptSelf, 80 RemoveDupFromSortedArray II, 75 Sort Colors
560 SubArrSumEqualsK, 1109 CorporateFlightBookings

• Hard

41 FirstMissingPositive, 862 ShortestSubArrWithSumAtLeastK

• Other

121 BestTimeToBuyAndSellStock, 122BTTBASS II, 123 BTTBASS III, 188 BTTBASS IV

• Binary search

4 MedianOf2SortedArrays, 34 Find1stLastPosOfElementInSortedArr, 35SearchInsertPosition
33 SearchInRotatedSortedArray, 81 SearchInRotatedSortedArray II, 153 FindMinimumInRotatedSortedArr

Stack, Priority Queue

155 Minimum Stack, 225 ImplementStackUsingQueues, 215 KthLargestElementInAnArray, 224 BasicCalculator, 295 FindMedianFromDataStream

Cycle

142 LinkedListCycleII, 287 FindTheDuplicateNumber, 457 Circular Arr Loop

List

• Easy

21 Merge2SortedLists, 83 RemoveDupfrom Sorted List, 141 LinkedListCycle, 206 Reverse Linked List, 160 IntersectionOf2LinkedList

• Medium
  

2 Add2Numbers, 19 RemoveNthNodeFromEndOfList, 24 SwapNodesInPairs, 61 Rotate List, 82 RemoveDupfrom Sorted List II, 86 Partition List
92 Reverse Linked List II
138 CopyListWithRandomPointer

• Hard

23 MergeKSortedLists, 25 ReverseNodesinK-Group

Tree

• Easy
  

100 Same Tree, 101 Symmetric Tree, 104 MaxDepthOfBinaryTree, 108 ConvertSortedArrToBST, 110 Balanced Binary Tree, 111 MinDepthOfBinaryTree, 112 PathSum,

572SubtreeOfAnotherTree, 572HasSubTree

• Medium
  

94 Binary Tree Inorder Traversal, 102 BinaryTreeLevelOrderTraversal
95 Unique BST II, 96 Unique BST, 98 Validate BST, 105 Construct BT From Preorder and Inorder, 113 PathSumII
114 FlattenBinaryTreeoLinkedList, 116 Populating NextRightPointersinEachNode, 117 116 II, 199 BinaryTreeRightSideView
426 ConvertBSTToOrderedDoublyLinkedList, 1008ConstructBSTFromPreorder

• Hard
  

99 Recover BST, 124 BinaryTreeMaximumPathSum, 297SerializeAndDeserializeBinaryTree

Graph

133 CloneGraph
207 Course Schedule, 210 Course Schedule II, 332 Reconstruct Itinerary

Sort

Sort

Design

146 LRU Cache

380 InsertDeleteGetRandomO(1), 535 EncodeAndDecodeTinyURL

Other

• Sliding window

3 LongestSubstringWithoutRepeatingCharacters, 76 MinimumWindowSubstring, 209 MinimumSubArrLen
239 SlidingWindowMaximum

1423 MaxPointsUCanObtainFromCards

• Bit Operation

201 BitwiseANDOfNumRange

• Matrix

48 Rotate Image 54 Spiral Matrix, 59 Spiral Matrix II, 73 SetMatrixZeroes, 74 Search2dMatrix, 240 Search2dMatrixII

• HashMap

30 SubstringWithConcatenationOfAllWords,49 Group Anagrams

• Math

31 Next Permute, 43 MultiplyStrings, 29 DivideTwoIntegers, 50 Pow(x, n), 69 Sqrt(x), 263 UglyNumber, 264 UglyNumberII, 326 PowerOfThree

• Parenthesis

20 ValidParenthesis, 22 Generate Parenthesis, 32 LongestValidParenthesis, 678 ValidParenthese

• N Sum

1 2Sum, 15 3Sum, 16 3SumClosest, 18 4Sum
2Sum II InputArrOrdered

• Palindrome

5 LongestPalindromSubstring, 9 PalindromeNumber, 336 PalindromePairs, 647 PalindromicSubstrings,

• Interval

57 InsertInterval, 56 MergeIntervals, 986 IntervalListIntersection

• Easy
  

7 ReverseInteger, 13 RomanToInt, 38 CountAndSay, 58 LenOfLastWord, 202 HappyNumber, 657 RobotReturnToOrigin

• Medium
  

6 ZigZag Conversion, 11 ContainerWithMostWater, 12 IntToRoman

71 Simplify Path
289 GameOfLife

• Hard
  

42 TrappingRainWater, 65 Valid Number, 68 TextJustification

Company

Goldman Sachs

Data Structure

# Definition for singly-linked list.
class ListNode(object):
    def __init__(self, x):
        self.val = x
        self.next = None