Java-practice

It will contain all logical problem and related concepts in Java.

`THIS REPO IS IN PROGRESS ...` 🚀 👨‍💻

Keep an 👁️ on it. I will be adding Data Structures and Algorithm implementaion along with problems related to the various DSA topics.

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.

All practice problems in this directory here.

NOTE: This is the premium conent.

Basic programs, pattern printing

Data Types in Java

Functions, 1D Array

2D Array

Strings

Recursion basic

Get Recursion

Print Recursion

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.

Basic Programs

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`

All GFG DSA contents

Arrays

Mathematics

Graphs

`Leetcode`

Explore Cards

Arrays

Monthly Challenges

August Challenge

October Challenge

May Challenge

Questions by difficulty order

Leetcode Tags

`Top Interview Questions`

root directory

Facebook

Frequent 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

`Codeforces`

CodingNinja