# SDE SHEET – A Complete Guide for SDE Preparation

**What is SDE Sheet?**

**SDE Sheet**is a list of the most important topics or the most popular questions that are asked in the Software Development Engineer Interviews.

- It doesn’t contain only coding questions.
- It covers all the segments round-wise like MCQs, DSA (Coding Questions), CS Subjects, Puzzles, System Design, Projects.
- It is helpful for both –
**Freshers and Experienced**.

**How is this sheet different or better from others?**

**Table of Contents/Roadmap**

- Build a Resume
- MCQs
- Aptitude and Reasoning
- Computer Science Subjects
- C
- C++
- Java
- Data Structures

- Algorithms
- OS
- DBMS
- CN

- CS Subjects
- Puzzles
- Projects
- System Design

**Build a Perfect Resume**The sole purpose of a resume is to make you land your dream job. It introduces your qualifications, skills, achievements, and everything regarding your expertise. It helps you land into your career. When you have a perfect resume, nothing can be a hindrance to the best job.

**Create and Know how to build a perfect Resume – Free Resume Builder By GeeksforGeeks – Create Resume Online**

**Multiple Choice Questions (MCQs)**

**Data Structures and Algorithms**

Keep a track of all the DSA problems mentioned below – Practice SDE Sheet

Check out the tutorial videos for all of the problems listed below – SDE Sheet Videos. We will continue to add videos on a daily basis.

**Arrays**

Question | Article | Practice | Video |
---|---|---|---|

Leaders in an array | View | Solve | Watch |

Equilibrium point | View | Solve | Watch |

Sort an array of 0s, 1s and 2s | View | Solve | Watch |

Reverse array in groups | View | Solve | Watch |

Convert array into Zig-Zag fashion | View | Solve | Watch |

Rearrange array alternatively | View | Solve | Watch |

Missing number in array | View | Solve | Watch |

K-th element of two sorted Arrays | View | Solve | Watch |

Check if two arrays are equal or not | View | Solve | Watch |

Kadane’s Algorithm | View | Solve | Watch |

Subarray with given sum | View | Solve | Watch |

Trapping Rain Water | View | Solve | Watch |

Minimum Platforms | View | Solve | Watch |

Stock buy and sell | View | Solve | Watch |

Largest Number formed from an Array | View | Solve | Watch |

Largest subarray with 0 sum | View | Solve | Watch |

Swapping pairs make sum equal | View | Solve | Watch |

**Searching and Sorting**

Question | Article | Practice | Video |
---|---|---|---|

Binary Search | View | Solve | Watch |

Quick Sort | View | Solve | Watch |

Merge Sort | View | Solve | Watch |

Merge two sorted arrays | View | Solve | Watch |

Inversion of Array | View | Solve | Watch |

Search in a Rotated Array | View | Solve | Watch |

Sorting Elements of an Array by Frequency | View | Solve | Watch |

Sum of Middle Elements of two sorted arrays | View | Solve | Watch |

K’th smallest element | View | Solve | Watch |

Allocate minimum number of pages | View | Solve | Watch |

**Hashing**

Question | Article | Practice | Video |
---|---|---|---|

First element to occur k times | View | Solve | Watch |

Find the element that appears once in sorted array | View | Solve | Watch |

Number of pairs | View | Solve | Watch |

Find all pairs with a given sum | View | Solve | Watch |

Common elements | View | Solve | Watch |

Find all four sum numbers | View | Solve | Watch |

Count distinct elements in every window | View | Solve | Watch |

Array Pair Sum Divisibility Problem | View | Solve | Watch |

Longest consecutive subsequence | View | Solve | Watch |

Array Subset of another array | View | Solve | Watch |

Zero Sum Subarrays | View | Solve | Watch |

Relative Sorting | View | Solve | Watch |

**Matrix**

Question | Article | Practice | Video |
---|---|---|---|

Rotate a matrix | View | Solve | Watch |

Spirally traversing a matrix | View | Solve | Watch |

Search in a row wise and column wise sorted matrix | View | Solve | Watch |

Print all palindromic paths from top left to bottom right in a matrix | View | Solve | Watch |

Find the row with maximum number of 1s | View | Solve | Watch |

Find median in row wise sorted matrix | View | Solve | Watch |

Check if all rows of a matrix are circular rotations of each other | View | Solve | Watch |

**String**

Question | Article | Practice | Video |
---|---|---|---|

Find first repeated character | View | Solve | Watch |

Reverse words in a given string | View | Solve | Watch |

Check if string is rotated by two places | View | Solve | Watch |

Roman Number to Integer | View | Solve | Watch |

Anagram | View | Solve | Watch |

Remove Duplicates | View | Solve | Watch |

Longest Distinct Characters in the string | View | Solve | Watch |

Implement Atoi | View | Solve | Watch |

Implement strstr | View | Solve | Watch |

Rabin Karp Algorithm | View | Solve | Watch |

KMP Algorithm | View | Solve | Watch |

Convert a Sentence into its equivalent mobile numeric keypad sequence. | View | Solve | Watch |

Longest Common Prefix | View | Solve | Watch |

Smallest window in a string containing all the characters of another string | View | Solve | Watch |

Uncommon characters | View | Solve | Watch |

Minimum indexed character | View | Solve | Watch |

**Recursion and Backtracking**

**Recursion:**The process in which a function calls itself directly or indirectly is called recursion and the corresponding function is called as recursive function.

**Backtracking:**Backtracking is an algorithmic-technique for solving problems recursively by trying to build a solution incrementally, one piece at a time, removing those solutions that fail to satisfy the constraints of the problem at any point of time (by time, here, is referred to the time elapsed till reaching any level of the search tree).

Question | Article | Practice | Video |
---|---|---|---|

Recursively remove all adjacent duplicates | View | Solve | Watch |

Tower Of Hanoi | View | Solve | Watch |

Special Keyboard | View | Solve | Watch |

Permutations of a given string | View | Solve | Watch |

N-Queen Problem | View | Solve | Watch |

Solve the Sudoku | View | Solve | Watch |

Rat in a Maze Problem | View | Solve | Watch |

Word Boggle | View | Solve | Watch |

Generate IP Addresses | View | Solve | Watch |

**Bit Manipulation**

Question | Article | Practice | Video |
---|---|---|---|

Find first set bit | View | Solve | Watch |

Rightmost different bit | View | Solve | Watch |

Check whether K-th bit is set or not | View | Solve | Watch |

Toggle bits given range | View | Solve | Watch |

Set kth bit | View | Solve | Watch |

Power of 2 | View | Solve | Watch |

Bit Difference | View | Solve | Watch |

Rotate Bits | View | Solve | Watch |

Swap all odd and even bits | View | Solve | Watch |

Count total set bits | View | Solve | Watch |

Longest Consecutive 1’s | View | Solve | Watch |

Sparse Number | View | Solve | Watch |

Alone in a couple | View | Solve | Watch |

Maximum subset XOR | View | Solve | Watch |

**Stack and Queue**

**Stack:**A stack is a linear data structure in which elements can be inserted and deleted only from one side of the list, called the top. A stack follows the LIFO (Last In First Out) principle.

**Queue:**A queue is a linear data structure in which elements can be inserted only from one side of the list called rear, and the elements can be deleted only from the other side called the front. The queue data structure follows the FIFO (First In First Out) principle.

Question | Article | Practice | Video |
---|---|---|---|

Parenthesis Checker | View | Solve | Watch |

Merge Overlapping Intervals | View | Solve | Watch |

Stock span problem | View | Solve | Watch |

Next larger element | View | Solve | Watch |

Largest Rectangular Area in a Histogram | View | Solve | Watch |

Queue using two Stacks | View | Solve | Watch |

Stack using two queues | View | Solve | Watch |

Get minimum element from stack | View | Solve | Watch |

LRU Cache | View | Solve | Watch |

Circular tour | View | Solve | Watch |

First non-repeating character in a stream | View | Solve | Watch |

Rotten Oranges | View | Solve | Watch |

Maximum of all subarrays of size k | View | Solve | Watch |

**Linked List**

Question | Article | Practice | Video |
---|---|---|---|

Finding middle element in a Linked list | View | Solve | Watch |

Reverse a Linked list | View | Solve | Watch |

Rotate a Linked List | View | Solve | Watch |

Reverse a Linked List in groups of given size | View | Solve | Watch |

Intersection point in Y shaped Linked lists | View | Solve | Watch |

Detect Loop in Linked list | View | Solve | Watch |

Remove loop in Linked List | View | Solve | Watch |

n’th node from end of Linked list | View | Solve | Watch |

Flattening a Linked List | View | Solve | Watch |

Merge two sorted Linked lists | View | Solve | Watch |

Pairwise swap of a Linked list | View | Solve | Watch |

Add two numbers represented by Linked lists | View | Solve | Watch |

Check if Linked List is Palindrome | View | Solve | Watch |

Implement Queue using Linked List | View | Solve | Watch |

Implement Stack using Linked List | View | Solve | Watch |

Given a Linked list of 0s, 1s and 2s, sort it | View | Solve | Watch |

Delete without head pointer | View | Solve | Watch |

**Binary Tree**

Question | Article | Practice | Video |
---|---|---|---|

Height of Binary Tree | View | Solve | Watch |

Number of leaf nodes | View | Solve | Watch |

Check if given Binary Tree is Height Balanced or Not | View | Solve | Watch |

Write Code to Determine if Two Trees are Identical or Not | View | Solve | Watch |

Given a binary tree, check whether it is a mirror of itself | View | Solve | Watch |

Maximum Path Sum | View | Solve | Watch |

Print Left View of Binary Tree | View | Solve | Watch |

Print Bottom View of Binary Tree | View | Solve | Watch |

Print a Binary Tree in Vertical Order | View | Solve | Watch |

Diameter of a Binary Tree | View | Solve | Watch |

Level order traversal in spiral form | View | Solve | Watch |

Connect Nodes at Same Level | View | Solve | Watch |

Convert a given Binary Tree to Doubly Linked List | View | Solve | Watch |

Serialize and Deserialize a Binary Tree | View | Solve | Watch |

**Binary Search Tree**

- The left subtree of a node contains only nodes with keys lesser than the node’s key.
- The right subtree of a node contains only nodes with keys greater than the node’s key.
- The left and right subtree each must also be a binary search tree.

Question | Article | Practice | Video |
---|---|---|---|

Check for BST | View | Solve | Watch |

Lowest Common Ancestor in a BST | View | Solve | Watch |

Ceil in BST | View | Solve | Watch |

K-th Largest Element in BST | View | Solve | Watch |

Largest BST in Binary Tree | View | Solve | Watch |

Merge Two Balanced Binary Search Trees | View | Solve | Watch |

Sorted Array to Balanced BST | View | Solve | Watch |

**Greedy Approach**

Question | Article | Practice | Video |
---|---|---|---|

Activity Selection | View | Solve | Watch |

N meetings in one room | View | Solve | Watch |

Coin Piles | View | Solve | Watch |

Maximize Toys | View | Solve | Watch |

Page Faults in LRU | View | Solve | Watch |

Largest number possible | View | Solve | Watch |

Minimize the heights | View | Solve | Watch |

Minimize the sum of product | View | Solve | Watch |

Huffman Decoding | View | Solve | Watch |

Minimum Spanning Tree | View | Solve | Watch |

**Dynamic Programming**

Question | Article | Practice | Video |
---|---|---|---|

Minimum number of Coins | View | Solve | Watch |

Longest Common Substring | View | Solve | Watch |

Longest Increasing Subsequence | View | Solve | Watch |

Longest Common Subsequence | View | Solve | Watch |

0 – 1 Knapsack Problem | View | Solve | Watch |

Maximum sum increasing subsequence | View | Solve | Watch |

Minimum number of jumps | View | Solve | Watch |

Edit Distance | View | Solve | Watch |

Coin Change Problem | View | Solve | Watch |

Subset Sum Problem | View | Solve | Watch |

Longest Palindrome in a String | View | Solve | Watch |

Form a Palindrome | View | Solve | Watch |

Box Stacking | View | Solve | Watch |

Rod Cutting | View | Solve | Watch |

Min Cost Path | View | Solve | Watch |

Minimum sum partition | View | Solve | Watch |

Count number of ways to cover a distance | View | Solve | Watch |

Egg Dropping Puzzle | View | Solve | Watch |

**Heap**

Question | Article | Practice | Video |
---|---|---|---|

Heap Sort | View | Solve | Watch |

Find median in a stream | View | Solve | Watch |

Operations on Binary Min Heap | View | Solve | Watch |

Rearrange characters | View | Solve | Watch |

Merge K sorted Linked lists | View | Solve | Watch |

Kth smallest element in a row-column wise sorted matrix | View | Solve | Watch |

**Graph**

Question | Article | Practice | Video |
---|---|---|---|

Depth First Traversal | View | Solve | Watch |

Breadth First Traversal | View | Solve | Watch |

Detect cycle in undirected graph | View | Solve | Watch |

Detect cycle in a directed graph | View | Solve | Watch |

Topological sort | View | Solve | Watch |

Find the number of islands | View | Solve | Watch |

Implementing Dijkstra | View | Solve | Watch |

Minimum Swaps | View | Solve | Watch |

Strongly Connected Components | View | Solve | Watch |

Shortest Source to Destination Path | View | Solve | Watch |

Find whether path exist | View | Solve | Watch |

Minimum Cost Path | View | Solve | Watch |

Circle of Strings | View | Solve | Watch |

Floyd Warshall | View | Solve | Watch |

Alien Dictionary | View | View | Watch |

Snake and Ladder Problem | View | Solve | Watch |

**Trie**

Question | Article | Practice | Video |
---|---|---|---|

Trie | (Insert and Search) | View | Solve | Watch |

Trie | (Delete) | View | Solve | Watch |

Print unique rows in a given Binary matrix | View | Solve | Watch |

Counting the number of words in a Trie | View | Solve | Watch |

Longest Common Prefix using Trie | View | Solve | Watch |

Auto-complete feature using Trie | View | Solve | Watch |

Boggle | Set 2 (Using Trie) | View | Solve | Watch |

Minimum XOR Value Pair | View | Solve | Watch |

Palindrome pair in an array of words (or strings) | View | Solve | Watch |

**Operating System**

**Below links contains complete Operating System Study Material:**

- Commonly Asked Operating Systems Interview Questions
- Last Minute Notes (LMNs) | Operating Systems
- Complete Tutorial on Operating System

**DBMS**

**Below Links contains complete DBMS study Material:**

- Commonly Asked DBMS Interview Questions
- Commonly Asked DBMS Interview Questions | Set-2
- Last Minute Notes (LMNs) | DBMS
- Complete Tutorial on DBMS

**SQL**

**Below Links contains complete SQL study Material:**

- SQL Interview Questions
- SQL Interview Questions | Set-2
- SQL Interview Questions | Set-3
- Complete Tutorial on SQL

**Computer Networks**

**Below Links contains complete Computer Networks study Material:**

- Commonly Asked Computer Networks Interview Questions
- Last Minute Notes (LMNs) | Computer Networks
- Complete Tutorial on Computer Networks

**Puzzles**

**Try to solve these**

**20 most popular puzzles asked in Interviews****Projects**

**If you haven’t made a project then take an idea from GFG Projects and start working on it.**

**System Design**

**System Design for tech interviews is something that can’t be ignored!**

Almost every IT giant whether it be Facebook, Amazon, Google, or any other ask various questions based on System Design concepts such as scalability, load-balancing, caching, etc. in the interview.

**This specifically designed System Design tutorial will help you to learn and master System Design concepts in the most efficient way from basics to advanced level.**

**Note: We will start uploading videos soon.**