Your personal guide to Software Development technical interviews.
Maintainer - Kevin Naughton Jr.
- A Linked List is a linear collection of data elements, called nodes, each pointing to the next node by means of a pointer. It is a data structure consisting of a group of nodes which together represent a sequence.
- Singly-linked list: linked list in which nodes have pointers to the next node
- Doubly-linked list: linked list in which nodes have pointers to both the previous node and the next node
- Time Complexity:
- Access:
O(n) - Search:
O(n) - Insert:
O(1) - Remove:
O(1)
- Access:
- A Stack is a collection of elements, with two principle operations: push, which adds to the collection, and pop, which removes the most recently added element
- Last in, first out data structure (LIFO)
- A Queue is a collection of elements, supporting two principle operations: enqueue, which inserts an element into the queue, and dequeue, which removes an element from the queue
- First in, first out data structure (FIFO)
- A Tree is an undirected, connected, acyclic graph
- A Binary Tree is a tree data structure in which each node has at most two children, which are referred to as the left child and right child
- Full Tree: a tree in which every node has either 0 or 2 children
- Perfect Binary Tree: a binary tree in which all interior nodes have two children and all leave have the same depth
- Complete Tree: a binary tree in which every level except possibly the last is full and all nodes in the last level are as far left as possible
- Binary Search Tree
- A binary search tree, sometimes called BST, is a type of binary tree which maintains the property that the value in each node must be greater than or equal to any value stored in the left sub-tree, and less than or equal to any value stored in the right sub-tree
- Time Complexity:
- Access:
O(log(n)) - Search:
O(log(n)) - Insert:
O(log(n)) - Remove:
O(log(n))
- Quicksort is a divide and conquer algorithm. It picks an element as a pivot and partitions the given array around the selected pivot. This process is repeated recursively for the left subarray and right subarray
- Stable: No
- Time Complexity:
- Best Case:
O(nlog(n)) - Worst Case:
O(n^2) - Average Case:
O(nlog(n))
- Mergesort is also a divide and conquer algorithm. It continuously divides an array into two halves, recurses on both the left subarray and right subarray and then merges the two sorted halves
- Stable: Yes
- Time Complexity:
- Best Case:
O(nlog(n)) - Worst Case:
O(nlog(n)) - Average Case:
O(nlog(n))
.
├── Array
│ ├── bestTimeToBuyAndSellStock.java
│ ├── findTheCelebrity.java
│ ├── gameOfLife.java
│ ├── increasingTripletSubsequence.java
│ ├── insertInterval.java
│ ├── longestConsecutiveSequence.java
│ ├── maximumProductSubarray.java
│ ├── maximumSubarray.java
│ ├── mergeIntervals.java
│ ├── missingRanges.java
│ ├── productOfArrayExceptSelf.java
│ ├── rotateImage.java
│ ├── searchInRotatedSortedArray.java
│ ├── spiralMatrixII.java
│ ├── subsetsII.java
│ ├── subsets.java
│ ├── summaryRanges.java
│ ├── wiggleSort.java
│ └── wordSearch.java
├── Backtracking
│ ├── androidUnlockPatterns.java
│ ├── generalizedAbbreviation.java
│ └── letterCombinationsOfAPhoneNumber.java
├── BinarySearch
│ ├── closestBinarySearchTreeValue.java
│ ├── firstBadVersion.java
│ ├── guessNumberHigherOrLower.java
│ ├── pow(x,n).java
│ └── sqrt(x).java
├── BitManipulation
│ ├── binaryWatch.java
│ ├── countingBits.java
│ ├── hammingDistance.java
│ ├── maximumProductOfWordLengths.java
│ ├── numberOf1Bits.java
│ ├── sumOfTwoIntegers.java
│ └── utf-8Validation.java
├── BreadthFirstSearch
│ ├── binaryTreeLevelOrderTraversal.java
│ ├── cloneGraph.java
│ ├── pacificAtlanticWaterFlow.java
│ ├── removeInvalidParentheses.java
│ ├── shortestDistanceFromAllBuildings.java
│ ├── symmetricTree.java
│ └── wallsAndGates.java
├── DepthFirstSearch
│ ├── balancedBinaryTree.java
│ ├── battleshipsInABoard.java
│ ├── convertSortedArrayToBinarySearchTree.java
│ ├── maximumDepthOfABinaryTree.java
│ ├── numberOfIslands.java
│ ├── populatingNextRightPointersInEachNode.java
│ └── sameTree.java
├── Design
│ └── zigzagIterator.java
├── DivideAndConquer
│ ├── expressionAddOperators.java
│ └── kthLargestElementInAnArray.java
├── DynamicProgramming
│ ├── bombEnemy.java
│ ├── climbingStairs.java
│ ├── combinationSumIV.java
│ ├── countingBits.java
│ ├── editDistance.java
│ ├── houseRobber.java
│ ├── paintFence.java
│ ├── paintHouseII.java
│ ├── regularExpressionMatching.java
│ ├── sentenceScreenFitting.java
│ ├── uniqueBinarySearchTrees.java
│ └── wordBreak.java
├── HashTable
│ ├── binaryTreeVerticalOrderTraversal.java
│ ├── findTheDifference.java
│ ├── groupAnagrams.java
│ ├── groupShiftedStrings.java
│ ├── islandPerimeter.java
│ ├── loggerRateLimiter.java
│ ├── maximumSizeSubarraySumEqualsK.java
│ ├── minimumWindowSubstring.java
│ ├── sparseMatrixMultiplication.java
│ ├── strobogrammaticNumber.java
│ ├── twoSum.java
│ └── uniqueWordAbbreviation.java
├── LinkedList
│ ├── addTwoNumbers.java
│ ├── deleteNodeInALinkedList.java
│ ├── mergeKSortedLists.java
│ ├── palindromeLinkedList.java
│ ├── plusOneLinkedList.java
│ ├── README.md
│ └── reverseLinkedList.java
├── Queue
│ └── movingAverageFromDataStream.java
├── README.md
├── Sort
│ ├── meetingRoomsII.java
│ └── meetingRooms.java
├── Stack
│ ├── binarySearchTreeIterator.java
│ ├── decodeString.java
│ ├── flattenNestedListIterator.java
│ └── trappingRainWater.java
├── String
│ ├── addBinary.java
│ ├── countAndSay.java
│ ├── decodeWays.java
│ ├── editDistance.java
│ ├── integerToEnglishWords.java
│ ├── longestPalindrome.java
│ ├── longestSubstringWithAtMostKDistinctCharacters.java
│ ├── minimumWindowSubstring.java
│ ├── multiplyString.java
│ ├── oneEditDistance.java
│ ├── palindromePermutation.java
│ ├── README.md
│ ├── reverseVowelsOfAString.java
│ ├── romanToInteger.java
│ ├── validPalindrome.java
│ └── validParentheses.java
├── Tree
│ ├── binaryTreeMaximumPathSum.java
│ ├── binaryTreePaths.java
│ ├── inorderSuccessorInBST.java
│ ├── invertBinaryTree.java
│ ├── lowestCommonAncestorOfABinaryTree.java
│ ├── sumOfLeftLeaves.java
│ └── validateBinarySearchTree.java
├── Trie
│ ├── addAndSearchWordDataStructureDesign.java
│ ├── implementTrie.java
│ └── wordSquares.java
└── TwoPointers
├── 3Sum.java
├── 3SumSmaller.java
├── mergeSortedArray.java
├── minimumSizeSubarraySum.java
├── moveZeros.java
├── removeDuplicatesFromSortedArray.java
├── reverseString.java
└── sortColors.java
18 directories, 124 files