Java-practice
It will contain all logical problem and related concepts in Java.
THIS REPO IS IN PROGRESS ... π π¨βπ»
Keep an
I AM WORKING EVERYDAY ON IT!
Learn about Google Interview Process
Directory Structure
Interview Prep
This directory has the solution to most of the famous coding interivew questions divided by topics from increasing order of difficulty and topics. If you are time bounded, you can start practicing problems from this section directly or else from below section.
NOTE: This is the premium conent.
- Basic programs, pattern printing
- Data Types in Java
- Functions, 1D Array
- 2D Array
- Strings
- Recursion basic
- Time and Space Complexity
- OOPS
- Collections in Java
- Stacks
- Queue
- Backtracking
- LinkedList
- Tree
- Interface and Generics
- Hashmaps
- Heap
- Tries
- Dynamic Programming
- Graph
- Segment Trees
- Bit Masking
- Generic Tree
- Binary Tree
For absolute beginner
You can start from this section and follow along. This section also covers Big O Analysis to start off.
Topic Highlights
Complexity analysis, Prime Ladder, Merge Sorted Array, Insert in Arrray, Wage Calculator, Unicode Characters, String operations, String matching, String split, Output Formatting, Keyboard input, Literal, Adder, Arithmetic operations, Data type size ranges
Data Structure and Algorithm Training
This directory covers from basic programming towards learning DSA. It was the part of my course taken from CodingBlocks live Data Structure and Algo batch.
NOTE: This is the premium conent. Find the topic that interests you from topic highlights section or else follow day wise. You can finish each day content in 1 day to keep you going and stay motivated. Don't overdo and don't underdo. Try to be as much consistent.
| Day wise Lesson | Topic Category | Topic Highlights |
|---|---|---|
| Day 1 | Basic Programming | Largest number, Loops demo, Function demo, Prime check, Simple interest, Sum of Natural numbers, Equal Remainder |
| Day 2 | Mathematics | GCD of two number, Nth Fibonacci, Prime Checking, Reverse Number |
| Day 3 | Pattern printing | square, left trianglular, right triangular, gunny, mirror, numeric triangular, numeric variation |
| Day 4 | Data types | Binary to Decimal, Data Types, Decimal to Binary, Temperature conversion |
| Day 5 | Arrays | Array Demo, Functions in Java, Maximum value in Array |
| Day 6 | Sorting & Searching | Bubble sort, Insertion sort, Selection sort, Linear Search, Reverse Array, Maximum sum of subarray |
| Day 7 | Strings & Arrays | ArrayList Demo, StringBuilder Demo, Strings Demo, String operations, 2D Array Demo, Spiral Print, Wave Print |
| Day 8 | Bit Manipulation | Bit masking, Count N bits, Extract Nth bit, Power of two check, Right most set bit, Turn ON Bit, Two unique elements in Array, Two missing element |
| Day 9 | Famous Algos | Maximum Subarray Sum, Kadane's Algo, Sieve of Eratosthenes, Sum of all sub-matrices, Merge Sorted Arrays |
| Day 10 | Recursion - I | Factorial, Nth Fibonacci, Linear Search Recursive, Move all X at End recursively, Power of N, Print Decreasing, Print Increasing, Print Decreasing Increasing, Print with Skip, isSorted Array |
| Day 11 | Recursion - II | Count Maze Path, String Permutations, Codes of String, Print Board Path, print Keypad Codes, Print Maze Path, Print String Subsequences |
| Day 12 | Recursion - III | N Queen problem, Permutation with Swap, Print Lexicographical Order, Tower of Hanoi, Maze path with Hurdles |
| Day 13 | Backtracking | Board Path with Ladders, Elephant total Paths, Suduko Solver, N Stairs Problem (ways to reach N stairs) |
| Day 14 | Searching & Sorting | Binary Search, First Index of N, Last Index of N, Maximum Height Ladder, Search in 2D matrix, Quick Sort, Merge Sort |
| Day 15 | OOPS, Exception Handling | Class, Objects, try catch demo, access specifier demo |
| Day 15.1 | OOPS, Stack | Class demo, constructor demo, getter setter, Static variables, instance variables, Object array, Stack using Array |
| Day 16 | OOPS, Queue | Access Specifier demo, Inheritance demo, Queue using Array, Absract demo, Polymorphism demo |
| Day 17 | Stack & Queues | Dynamic Stack, Dynamic Queue, Queue using Stack enqueue efficient, Balance Paranthesis, Reverse Queue, Reverse Stack, Next Greater Element, Stack using Array, Queue using Array |
| Day 18 | LinkedList | LinkedList implementation, Reverse LinkedList by reversing data iteratively, pointer recursively, list data by pointer |
| Day 19 | LinkedList, Stack, Queues | Kth Node from Last Node, Count Distinct Rectangles, Detect cycle in LL, Revese LL, MergeSort to LL, Mid of LL |
| Day 20 | Binary Tree | Binary Tree implementation, find element, height of BT, max data in BT, min data in BT, mirror BT, size of BT, Tree Traversals (preorder, inorder, postorder) |
| Day 21 | Binary Tree | Diameter of tree, checks Balanced Tree, Left view, Right view, Root to Leaf traversal, Sum of Leaf nodes, Level order Traversals, |
| Day 22 | HashMap & Generics | Hashmap demo, Generic concept demos |
| Day 23 | Heaps | Heap implementation |
| Day 24 | Dynamic Programming | Fibonacci problem iterative, recursive, DP approach |
| Recursion | Recursion | Bubble Sort, N Factorial, First Index, Last Index, Nth Fibonacci, Power of N, Print skip Decreasing Increasing, check Sorted Array, print Increasing, print Decreasing, Sum of N terms |
GeeksForGeeks
Leetcode
Explore Cards
Monthly Challenges
Questions by difficulty order
Leetcode Tags
Top Interview Questions
Question set from Interview Prep directory
| SN. | Topics, DSA | Practice Questions |
|---|---|---|
| 1 | Basic Programming | various Pattern printing, Mathematical problems, Fibonacci Series, GCD, Prime number, Reverse number, Sum N Natural numbers, else if demo |
| 2 | Data types | Temperature table, upper or lower case check |
| 3 | Functions, 1D Array, Number System, Searching, Sorting | Linear Search, Binary Search, Insertion Sort, Selection Sort, Bubble Sort, Base conversion problems, Upper & Lower index of search element, Maximum value in Array |
| 4 | 2D Array | 2D Array demo, Wave pattern printing, Spiral wave print |
| 5 | Strings & StringBuilder | String demo, StringBuilder demo, Print all Substrings, Print Characters in String |
| 6 | Recursion | Bubble Sort, Factorial, First & Last Index in Array, isSorted Array, Nth Fibonacci, Pattern printing, Power of N, Search all indices of item, Print Decreasing, Print Increasing, Print Decreasing Increasing Skip, Print Decreasing Increasing |
| 7 | Get Recursion | Print all Permutations of String, Maze Path, Maze Path Diagonal, Board Path, Get all Subsequences of String |
| 9 | Print Recursion | Print Board Path, Print Maze Path, Print Maze Path Diagonal, Print N Queens, Print Subsequences, Count Board Path, Count Maze Path, Count Maze Path Diagonal, Count N Queens |
| 10 | Time & Space Complexity | Merge Sort, Quick Sort, Power N optimal, Sieve of Eratosthenes, Dutch National Flag problem |
| 11 | Stacks | implement Stack using Array, Reverse Stack, Next greater element in Array |
| 12 | Stack & Queue | Implement Queue using Array, Stack & LinkedList, Reverse Queue, Stack using Queue Push & Pop Efficient, Queue using Stack Enqueue & Dequeue Efficient, Maximum in each Subarray of Window K, First Non-repeating Character, First Negative number in every subarray of size K |
| 13 | Backtracking | N Queens, N Knights, N Queen Generic, Queen Permutations, Queen Combinations, Queen Combination with Killing, Coin Change Permutations, Coin Change Combinations, Blocked Maze Path |
| 14 | LinkedList | implement LinkedList, Stack using LL, Queue using LL |
| 15 | Tree | implement Binary Tree, Generic Tree, Binary Search Tree |
| 16 | Interface & Generics | Generics demo, Dynamic Stack, Bubble Sort Generic, Comparator demo |
| 17 | HashMap | implement HashMap from scratch, Collections, Subarray sum zero problem, Array Intersection, Generic LinkedList, Maximum Frequency Character |
| 18 | Heap | implement Heap from scratch with various operations |
| 19 | Tries | implement Trie, Heap Generic, Huffman Encoder for Space optimization |
| 20 | Dynamic Programming | Board Path, Count Board Path, Count Binary Strings, Dungeon Game, Edit Distance problem, Fibonacci, LCS, K Ordered LCS, Knapsack problem, LCS of 3 Strings, Longest Increasing Subsequence, Longest Palindromic Subsequence, Matrix Chain Multiplication, Maze Path, Maze Path Diagonal, Mixture Colors, Palindrome Partitioning, Unique BST Counts, Wildcard Pattern Matching, Wine Problem (4 approaches to most of the problems) |
| 21 | Graph | implement Graph from scratch, all Graph realted algorithms & problems |
| 22 | Segment Tree | implement Segment Tree |
| 23 | Bit Masking/Bit Magic | Add One, check Power of 2, check Even Odd, Extract Bit, Missing 2 Numbers, ith Magic Number, Pascal sum, Reset Bit, Rightmost Set Bit, Set ith Bit, Unique Element |
| 24 | Generic Tree | implement Generic Tree from scratch, various problems on it |
| 25 | Binary Tree | implement Binary Tree from scratch, various problems on it |
| 26 | Java Collections | Maps, Set, Vector, Queue Interface demos |
| 27 | OOPS | OOPS demo |