For Service-Based Companies

1. Arrays

In DSA we will start with arrays. Arrays are the building block of Data structures and algorithms. You must solve at least 30-40 questions on arrays. You might think these are a lot of questions, but they aren’t. It will help you if you make your concepts strong in an array because it is used almost everywhere. You must thoroughly practice logical questions from the array.

Sample Questions: 

• Program to Reverse the Array
• Find a Peak Element that is Not Smaller than its Neighbors
• Find the Kth Largest and Kth Smallest Number in an Array
• Write a Program to Sort the Given Array
• Write a Program to Sort an Array of 0s, 1s, and 2s
• Trapping Rain Water

To Practice, more questions on Array, refer to Array GFG Practice.

2. Strings

The next most important topic is Strings. You should practice at least 30-40 questions in order to grasp the concept in a good manner. If you are thinking by doing only some specific or standard questions, you will be able to crack the placement, then it is a clear myth as the placement requires your thought process and problem-solving techniques.

Sample Questions: 

• Program to Check Whether the Number is Palindrome or Not
• Longest Valid Parenthesis
• Check Whether Two Strings are Anagrams of Each Other
• Write a Program to Print all Permutations of a Given String

To Practice, more questions on Strings, refer to String GFG Practice.

3. Recursion

Next comes – Recursion. It is one of the most important topics because it has many use cases like LinkedList, graph, DP, etc. You should understand Recursion well and you have to solve 30-40 problems in order to make a strong grip on recursion. Why only 20-25 questions, as recursion is used in further concepts as well so there you can learn more about it?

Sample Questions:

• Program to Calculate pow(x, n)
• Print Sums of All Subsets of a Given Set
• Program for Tower of Hanoi Algorithm
• Print all Non-Increasing Sequences of a Sum Equal to a Given Number x
• Find Ways an Integer can be Expressed as the Sum of the n-th Power of Unique Natural Numbers
• Recaman’s Sequence

To Practice, more questions on Recursion, refer to Recursion GFG Practice

4. Linked List

After recursion, you may now jump to the LinkedList. Here, you will learn about dynamic memory allocation. Linked lists will be very useful in trees. About the questions, you must solve 30-40 questions.

Sample Questions:

• Print the Middle of a Given Linked List
• Flattening a Linked List
• Detect Loop in a Linked List
• Remove Duplicate Elements From the Sorted Linked List
• Rotate a Linked List
• Delete the Last Occurrence of an Item From the Linked List
• Delete the Elements in a Linked List Whose Sum is Equal to Zero

To Practice, more questions on Linked List, refer to Linked List GFG Practice

5. Stack and Queues

The next comes – Stack and Queues. You must solve 20 questions on each topic. You should also know the application of Stack and Queues. You will use these concepts in the future as well, so better you do it in a better way. You must understand how Stack and Queue are created.

Sample Questions:

• Reverse a Stack Using Recursion
• Sort a Stack Using Recursion
• Sort a Stack Using a Temporary Stack
• Reverse a Stack Without Using Extra Space In O(N)
• Delete The Middle Element of a Stack
• Sorting an Array Using Stacks
• Delete Array Elements That Are Smaller Than The Next Or Become Smaller
• Check If a Queue Can Be Sorted Into Another Queue Using a Stack
• Reverse Individual Words
• Count Subarrays Where The Second Highest Lies Before The Highest
• Check If an Array is Stack Sortable

To Practice, more questions on Stack and Queues, refer to Stack and Queues GFG Practice

6. Hashing

Hashing is again a must-go-through topic when it comes to learning DSA. Like other topics, it is also an important topic. You must understand its working, its complexities, and its usage in programming. It has better time complexity hence is very important to practice. About the questions, you must solve 20-30 questions on Hashing.

Sample Questions:

• Find Whether an Array is a Subset of Another Array
• Union And Intersection of Two Linked Lists
• Find a Pair With the Given Sum
• LRU Cache Implementation
• Find the Itinerary From a Given List of Tickets
• Find Four Elements A, B, C, And D in an Array Such That A+B = C+D
• Find the Largest Subarray With 0 Sum

To Practice, more questions about Hashing, refer to Hashing GFG Practice

7. Greedy Algorithms

Next, you may proceed with Greedy algorithms as it has a great role in the Dynamic Programming concept. The advantage of comprehending Greedy algorithms is that you will learn how to think about a particular problem. Greedy algorithms are often used as a brute-force approach. Sometimes, we get optimized solutions using brute force approaches. About the questions, you must solve at least 30-35 questions on Greedy.

Sample Questions:

• Activity Selection Problem
• Kruskal’s Minimum Spanning Tree Algorithm
• Huffman Coding
• Efficient Huffman Coding For Sorted Input
• Prim’s Minimum Spanning Tree Algorithm
• Prim’s Mst For Adjacency List Representation
• Dijkstra’s Shortest Path Algorithm

To Practice, more questions on Greedy Algorithms, refer to Greedy Algorithms GFG Practice

8. Algorithms

After this, you can now jump to solve Algorithm questions. Algorithms are the core of programming helping to develop optimized methods with a good time and space complexity is itself one of the most important skills. Although there is no such number to be called sufficient for algorithms but about 40-50 questions can well develop anyone’s algorithmic skills in programming.

Sample Questions:

• Search Pattern (Kmp-Algorithm) 
• Search Pattern (Rabin-Karp Algorithm)
• Search Pattern (Z-Algorithm)
• Search an Element in a Sorted and Rotated Array(Binary Search)
• A Median of Two Sorted Arrays(Binary Search)
• Maximum And Minimum of an Array Using a Minimum Number Of Comparisons
• K Largest(Or Smallest) Elements in an Array | Added Min Heap Method
• Find the Number of Pairs (X, Y) In an Array Such That X^Y > Y^X

To Practice, more questions on Algorithms, refer to Algorithms GFG Practice

The amount of coding required for placements will depend on the specific job you are applying for. In general, technical roles such as software engineering, data science, or web development will require a significant amount of coding knowledge and experience.

Have you ever seen people on LinkedIn getting placed at big tech companies? Well, If you are here, we will make sure you also post the same. ???

Before going directly to how much coding, We should understand the fact that Why Coding?

Many times the student is confused, that Why we need to solve such problems that are of no use, Why do we need to learn DSA or Problem-solving? So the answer to this question is very simple. The organization to which you are going to apply is seeking a candidate who is logically strong and technically sound. They want a person who can implement the fundamentals of computer programming into physical entities and solve real-life problems.

It’s worth noting that some companies may have specific coding languages or frameworks that they use, so it’s a good idea to research the company and its technology stack before applying to ensure you have the necessary skills.

For the same cause, it becomes necessary for an individual to learn coding in order to get placed.

But Don’t worry, to get you placed in your dream company, we are here with a well-planned strategy and valuable resources. If you are a computer science student or want to work in the tech industry, you must be familiar with coding. However, the question here is exactly-