A Step by Step Guide for Placement Preparation all IT companies

On-Campus placement, Off placement Checklist procedure

The key to crack the campus placements, Placement Preparation Strategy for Product, Service, and Analytics-Based Companies.

Start preparing for your dream placement, Before it’s too late!

Data Structures:

 

  1. Array
    1. Kadane’s Algorithm

https://www.geeksforgeeks.org/largest-sum-contiguous-subarray/ 

  1. N/2, N/3 greatest Number

https://leetcode.com/problems/majority-element/ 

https://leetcode.com/problems/majority-element-ii/ 

https://www.geeksforgeeks.org/given-an-array-of-of-size-n-finds-all-the-elements-that-appear-more-than-nk-times/ 

  1. Merge overlapping intervals

https://leetcode.com/problems/merge-intervals/ 

  1. Rotate matrix

https://leetcode.com/problems/rotate-image/ 

  1. Buy / Sell stocks – I, II, III: https://leetcode.com/problems/best-time-to-buy-and-sell-stock/
  1. String
    1. Pattern matching algorithms (KMP + Rabin Karp)

https://www.geeksforgeeks.org/kmp-algorithm-for-pattern-searching/ 

https://www.geeksforgeeks.org/rabin-karp-algorithm-for-pattern-searching/ 

  1. Using StringBuilder class -> Add, Multiply Strings

https://www.geeksforgeeks.org/stringbuilder-class-in-java-with-examples/

https://www.geeksforgeeks.org/stringbuilder-append-method-in-java-with-examples/ 

 

  1. String compression algorithm

https://leetcode.com/problems/string-compression/ 

 

  1. LinkedList
    1. Implementation of Linkedlist

https://www.geeksforgeeks.org/implementing-a-linked-list-in-java-using-class/ 

https://leetcode.com/problems/design-linked-list/ 

  1. Detect cycle in a linkedlist – Floyd Algo

https://leetcode.com/problems/linked-list-cycle/ 

  1. Reverse a linked list + reverse in groups

https://leetcode.com/problems/reverse-linked-list/ 

https://leetcode.com/problems/reverse-nodes-in-k-group/ 

  1. Stack
    1. Implementation of Stack

https://www.geeksforgeeks.org/stack-data-structure-introduction-program/

https://www.geeksforgeeks.org/stack-class-in-java/ 

  1. Balance parenthesis

https://leetcode.com/problems/valid-parentheses/

  1. Trapping rain water

https://leetcode.com/problems/trapping-rain-water/ 

  1. Implement min stack

https://leetcode.com/problems/min-stack/ 

 

  1. Queue
    1. Implementation of Queue + Deque

https://www.geeksforgeeks.org/queue-set-1introduction-and-array-implementation/

https://www.geeksforgeeks.org/queue-interface-java/ 

https://www.geeksforgeeks.org/implementation-deque-using-circular-array/

https://www.geeksforgeeks.org/deque-interface-java-example/

 

  1. Sliding window maximum

https://leetcode.com/problems/sliding-window-maximum/ 

  1. Implement BFS 

https://www.geeksforgeeks.org/breadth-first-search-or-bfs-for-a-graph/ 

  1. Implement Level order in Binary tree

https://leetcode.com/problems/binary-tree-level-order-traversal/ 

 

  1. PriorityQueue or Heap
    1. Implementation of Heap Data structure

https://www.geeksforgeeks.org/heap-data-structure/ 

  1. Connect n ropes with min cost: https://www.geeksforgeeks.org/connect-n-ropes-minimum-cost/
  2. Median of running stream: https://www.geeksforgeeks.org/median-of-stream-of-running-integers-using-stl/
  3. LRU and LFU cache

https://leetcode.com/problems/lru-cache/ 

https://leetcode.com/problems/lfu-cache/ 

 

  1. Set & Map
    1. Internal working of HashMap

https://www.geeksforgeeks.org/internal-working-of-hashmap-java/ 

  1. 4-sum

https://leetcode.com/problems/4sum/ 

  1. Longest substring without repeat: https://www.interviewbit.com/problems/longest-substring-without-repeat/
  1. Binary Tree
    1. Implementation: insert, delete, traverse: https://youtu.be/wYT3hsc1XMs
    2. Print top view, left view, right view, bottom view, level order, zig-zag traversal of Binary tree

https://www.geeksforgeeks.org/print-nodes-top-view-binary-tree/ 

https://www.geeksforgeeks.org/print-left-view-binary-tree/   

https://leetcode.com/problems/binary-tree-right-side-view/ 

https://www.geeksforgeeks.org/bottom-view-binary-tree/ 

https://www.geeksforgeeks.org/level-order-tree-traversal/

https://leetcode.com/problems/binary-tree-zigzag-level-order-traversal/ 

  1. Invert a binary tree: https://leetcode.com/problems/invert-binary-tree/
  2. Lowest common ancestor

https://leetcode.com/problems/lowest-common-ancestor-of-a-binary-tree/ 

 

  1. Binary Search Tree
    1. Implementation

https://www.geeksforgeeks.org/binary-search-tree-set-1-search-and-insertion/ 

 

  1. Check if a tree is BST or not

https://www.geeksforgeeks.org/a-program-to-check-if-a-binary-tree-is-bst-or-not/ 

  1. AVL tree and rotation

https://www.geeksforgeeks.org/avl-tree-set-1-insertion/ 

https://www.geeksforgeeks.org/avl-tree-set-2-deletion/ 

 

  1. Graph
    1. Implementation, BFS and DFS traversals

https://www.geeksforgeeks.org/graph-and-its-representations/ 

https://www.geeksforgeeks.org/breadth-first-search-or-bfs-for-a-graph/ 

https://www.geeksforgeeks.org/depth-first-search-or-dfs-for-a-graph/ 

  1. Topological sorting

https://www.geeksforgeeks.org/topological-sorting/ 

  1. Bellman ford Algorithm

https://www.geeksforgeeks.org/bellman-ford-algorithm-dp-23/ 

  1. Dijkstra’s Algorithm

https://www.geeksforgeeks.org/dijkstras-shortest-path-algorithm-greedy-algo-7/ 

  1. Prim’s Algorithm

https://www.geeksforgeeks.org/prims-minimum-spanning-tree-mst-greedy-algo-5/ 

  1. Kruskal’s Algorithm

https://www.geeksforgeeks.org/kruskals-minimum-spanning-tree-algorithm-greedy-algo-2/ 

  1. Unique Islands Problem: https://www.geeksforgeeks.org/find-the-number-of-distinct-islands-in-a-2d-matrix/

 

  1. Trie
    1. Implementation

https://www.geeksforgeeks.org/trie-insert-and-search/ 

  1. Segment Trees : More important in CP
    1. Implementation

https://www.hackerearth.com/practice/data-structures/advanced-data-structures/segment-trees/tutorial/

 

Algorithms:

 

  1. Two pointers Algorithm
    1. 3-Sum

https://leetcode.com/problems/3sum/ 

  1. Container with most water

https://leetcode.com/problems/container-with-most-water/ 

  1. Sort the array containing only 0, 1 and 2

https://www.geeksforgeeks.org/sort-an-array-of-0s-1s-and-2s/ 

  1. Math
    1. Fast Power: https://www.youtube.com/watch?v=dyrRM8dTEus
    2. Euclid GCD: https://www.geeksforgeeks.org/euclidean-algorithms-basic-and-extended/ 
    3. Sieve of Eratosthenes:

https://www.geeksforgeeks.org/sieve-of-eratosthenes/ 

  1. Recursion + Backtracking
    1. Sudoku solver

https://leetcode.com/problems/sudoku-solver/ 

  1. N-Queens Problem

https://leetcode.com/problems/n-queens/ 

  1. Permutation and Combinations (Bruteforce)

https://www.geeksforgeeks.org/permutation-and-combination/ 

  1. Bits Manipulation + Mathematics
    1. Find one  non-repeating number, find two

https://www.geeksforgeeks.org/non-repeating-element/ 

https://www.geeksforgeeks.org/find-two-non-repeating-elements-in-an-array-of-repeating-elements/ 

  1. Count 1 bits in a number

https://leetcode.com/problems/number-of-1-bits/ 

  1. Divide & Conquer
    1. Merge Sort

https://www.geeksforgeeks.org/merge-sort/ 

  1. Median of two sorted arrays

https://leetcode.com/problems/median-of-two-sorted-arrays/ 

 

  1. Binary Searching
    1. Find upper and lower bound using Binary search

https://www.geeksforgeeks.org/find-first-and-last-positions-of-an-element-in-a-sorted-array/ 

  1. Allocate books: https://www.interviewbit.com/problems/allocate-books/
  1. Greedy Programming
    1. Candy distribution: https://www.interviewbit.com/problems/distribute-candy/
    2. Gas station: https://www.interviewbit.com/problems/gas-station/
    3. Fractional Knapsack

https://www.geeksforgeeks.org/fractional-knapsack-problem/ 

  1. Dynamic Programming
    1. 0/1 Knapsack:https://youtu.be/xCbYmUPvc2Q
    2. Longest increasing subsequence

https://leetcode.com/problems/longest-increasing-subsequence/ 

  1. Matrix chain multiplication

https://www.geeksforgeeks.org/matrix-chain-multiplication-dp-8/ 

  1. Coin change problem

https://leetcode.com/problems/coin-change/ 

 

Operating System:

  1. Basics of Threads
  2. Process scheduling algorithms
  3. Critical section Problem
  4. Deadlock
  5. Memory management
    1. Paging
    2. Segmentation
  6. Page replacement algorithms
  7. Disk scheduling algorithms

 

DBMS:

  1. Types of Keys: Candidate, Super, Foriengn keys
  2. Normal Forms
  3. Joins
  4. SQL queries
  5. ACID properties
  6. Indexing: B trees, B+ trees concepts

System design:

 

  1. Low-level design
    1. Class, ER diagrams
    2. OOPS concepts
    3. Design Elevator system, Parking Lot, MakeMyTrip System
  2. High-level design
    1. Scaling
    2. Distributed systems
    3. Microservice and Monolithic architecture
    4. Load balancing
    5. Message queue
    6. Design Whatsapp, Tinder, Uber system