Interview

You don’t need to master all of DSA to prepare effectively for TCS NQT. You need to master the right patterns, practice under time pressure, and understand where to spend your limited preparation time.

Preparing for TCS NQT can feel overwhelming.

You search online and find hundreds of coding questions. Then you see lists covering arrays, linked lists, stacks, queues, trees, graphs, dynamic programming, and competitive programming.

The natural reaction is:

“I need to learn everything before the exam.”

You don’t.

If you have only 10 days, your goal should not be to become an expert competitive programmer. Your goal should be to maximize your probability of solving the questions that are most aligned with the type of problems you are likely to encounter.

I analyzed a collection of TCS NQT previous papers and coding preparation material available in the TCS NQT PYQ repository. The repository contains multiple previous-paper collections, a set of 50 basic coding problems, and DSA-pattern-oriented material.

The biggest lesson from this analysis is simple:

Prioritize problem patterns over problem count.

This article presents a focused 10-day TCS NQT study plan covering coding, aptitude, verbal ability, and mock-test practice.


1. What Should You Prioritize?

Before creating a study plan, let’s answer the most important question:

What should you actually study?

Based on the PYQ and preparation material, I would divide the preparation into three levels.

Tier 1 — Highest Priority

These topics deserve most of your preparation time.

  • Number manipulation
  • Strings
  • Arrays
  • Frequency counting
  • Hashing
  • Searching
  • Sorting
  • Basic mathematics
  • Time, speed and distance
  • Time and work
  • Percentages
  • Profit and loss
  • Ratios and averages

Tier 2 — Important

These should be covered after Tier 1.

  • Matrix problems
  • Two pointers
  • Sliding window
  • Recursion
  • Basic linked lists
  • Basic stack and queue

Tier 3 — Lower Priority

These are useful for broader DSA preparation but should not dominate a 10-day TCS NQT plan.

  • Advanced trees
  • Graph algorithms
  • Dynamic programming
  • Complex backtracking
  • Advanced greedy algorithms

This doesn’t mean these topics can never appear in a coding test.

It means that when you have only 10 days, you should prioritize topics that give you the highest return on preparation time.


2. The 10-Day Strategy

Your preparation should follow this progression:

Days 1–3
Build Coding Fundamentals
Days 4–6
Learn Reusable Coding Patterns
Days 7–8
Solve Previous-Year Questions
Day 9
Full Mock Tests
Day 10
Revision + Weak Areas

At the same time, you should practice aptitude and verbal ability every day.

A good daily split is:

Coding 3 hours
Quantitative 2 hours
Reasoning 1 hour
Verbal 1 hour
Revision 1 hour

You don’t have to follow this exact schedule.

The important thing is to touch coding every day and avoid spending all your time on one section.


Day 1 — Master Number-Based Coding

The first day should focus on basic programming logic.

Solve problems involving:

  • Even or odd
  • Prime number
  • Factorial
  • Fibonacci
  • Reverse a number
  • Palindrome number
  • Armstrong number
  • Sum of digits
  • GCD
  • LCM
  • Perfect number
  • Strong number
  • Automorphic number

The goal isn’t to memorize 12 solutions.

The goal is to understand a few fundamental operations:

digit = n % 10
n = n // 10

These two operations appear repeatedly in number-based problems.

For example, reversing a number follows this pattern:

rev = 0
while n > 0:
digit = n % 10
rev = rev * 10 + digit
n //= 10

Once you understand this pattern, you can solve several variations:

  • Reverse a number
  • Check palindrome
  • Calculate digit sum
  • Count digits
  • Find product of digits
  • Find largest digit

Aptitude Focus

Study:

  • Percentages
  • Ratios
  • Averages
  • Profit and loss

Goal for Day 1

You should be able to solve basic number problems without looking at solutions.


Day 2 — Strings

Day 2 is dedicated to string manipulation.

Practice:

  1. Reverse a string
  2. Check palindrome
  3. Count vowels
  4. Count consonants
  5. Count words
  6. Remove spaces
  7. Remove duplicate characters
  8. Character frequency
  9. Check anagram
  10. Find first non-repeating character
  11. Reverse words
  12. Find the longest word

The most important concept here is frequency counting.

Whenever you see words like:

frequency
duplicate
repeated
unique
occurrence

Think about a dictionary or Counter.

from collections import Counter
freq = Counter(s)

For example:

s = "programming"
freq = Counter(s)
print(freq)

This basic idea can solve many variations.

Aptitude Focus

Study:

  • Number systems
  • HCF and LCM
  • Simple interest
  • Compound interest

Verbal Focus

Practice:

  • Error identification
  • Sentence correction
  • Fill in the blanks

Goal for Day 2

You should become comfortable converting a natural-language string problem into simple loops and frequency logic.


Day 3 — Arrays

Arrays are one of the most important topics to prepare.

Start with:

  • Largest element
  • Smallest element
  • Second largest
  • Second smallest
  • Array sum
  • Array average
  • Reverse array
  • Check if sorted
  • Count frequency
  • Find duplicates
  • Find missing number

Then move to:

  • Move zeros to the end
  • Rotate an array
  • Merge two arrays
  • Find intersection
  • Find union

One particularly important problem is:

Find the Missing Number

If the array contains numbers from 1 to N with one missing:

expected = n * (n + 1) // 2
actual = sum(arr)
missing = expected - actual

This is a classic example of recognizing a mathematical pattern instead of using nested loops.

Aptitude Focus

Study:

  • Time and work
  • Pipes and cisterns
  • Time, speed and distance

Reasoning Focus

Practice:

  • Number series
  • Coding-decoding
  • Blood relations
  • Direction sense

Goal for Day 3

You should be able to solve basic array problems using:

  • Iteration
  • Sorting
  • Hashing
  • Mathematical formulas

Day 4 — Searching and Sorting

Today, learn the fundamental searching and sorting algorithms.

Searching

Understand:

  • Linear search
  • Binary search

The key difference is simple.

Linear Search

Check every element
O(N)

Binary Search

Repeatedly divide the search space
O(log N)

But remember:

Binary search requires a sorted search space.

Practice:

  • Search for an element
  • Find first occurrence
  • Find last occurrence
  • Count occurrences
  • Find insertion position

Sorting

Understand:

  • Bubble sort
  • Selection sort
  • Insertion sort

You don’t necessarily need to implement advanced sorting algorithms from scratch for basic TCS-style preparation.

Focus on understanding:

  • How sorting works
  • When sorting simplifies a problem
  • Time complexity

Aptitude Focus

Study:

  • Permutations
  • Combinations
  • Probability

Verbal Focus

Practice:

  • Reading comprehension
  • Vocabulary
  • Sentence completion

Goal for Day 4

You should recognize when a problem can be simplified by sorting.


Day 5 — Learn the Most Useful DSA Patterns

Today is about pattern recognition.

Instead of solving 20 unrelated problems, learn a few reusable patterns.

Pattern 1: Hashing

Useful for:

  • Two Sum
  • Frequency counting
  • Duplicate detection
  • Anagrams
  • First unique element

Typical approach:

freq = {}
for x in arr:
freq[x] = freq.get(x, 0) + 1

Pattern 2: Two Pointers

Useful for:

  • Pair sum
  • Palindrome
  • Reversing arrays
  • Removing duplicates

Basic structure:

left = 0
right = len(arr) - 1
while left < right:
# process

Pattern 3: Sliding Window

Useful for:

  • Maximum sum subarray of size K
  • Longest substring
  • Fixed-size window problems

Example:

window_sum = sum(arr[:k])
answer = window_sum
for i in range(k, len(arr)):
window_sum += arr[i]
window_sum -= arr[i - k]
answer = max(answer, window_sum)

Pattern 4: Kadane’s Algorithm

Used for:

Maximum sum contiguous subarray

Core idea:

current = arr[0]
best = arr[0]
for x in arr[1:]:
current = max(x, current + x)
best = max(best, current)

The key question is:

Should I extend the current subarray or start a new one?


Day 6 — Matrix + Basic Data Structures

Today, cover matrix problems.

Practice:

  • Matrix addition
  • Matrix subtraction
  • Transpose
  • Diagonal sum
  • Boundary traversal
  • Spiral traversal
  • Matrix rotation

Then spend a small amount of time on basic data structures.

Stack

Know:

  • Push
  • Pop
  • Peek
  • Balanced parentheses

Queue

Know:

  • Enqueue
  • Dequeue
  • Basic implementation

Linked List

Know:

  • Traversal
  • Insertion
  • Deletion
  • Reverse linked list

You don’t need to spend half a day learning advanced linked-list tricks.

Understand the fundamentals.

What about Trees?

For a 10-day plan, learn only:

  • Binary tree terminology
  • Inorder traversal
  • Preorder traversal
  • Postorder traversal
  • Level-order traversal
  • Basic BST search

What about Graphs and Dynamic Programming?

If you have never studied them, don’t let them consume your preparation time.

You have limited time.

Focus on maximizing your score from the topics you can realistically master.


Day 7 — Previous-Year Questions

Now stop learning new topics.

Start solving actual previous-year questions.

Use the available PYQ collections from the repository and classify every question into a pattern.

For example:

Question
Number?
String?
Array?
Hashing?
Sorting?
Matrix?
Two Pointer?
Other?

Create a simple table:

QuestionTopicPatternSolved?Time
Q1ArrayFrequencyYes8 min
Q2StringAnagramYes6 min
Q3NumberDigit logicNo15 min

This is much more useful than simply counting how many questions you solved.

The goal is to identify your weak patterns.


Day 8 — PYQ Simulation

Today, simulate the real exam environment.

Choose a set of previous questions.

Set a timer.

No Google.

No ChatGPT.

No solution lookup.

No hints.

Solve under exam conditions.

After finishing, classify every mistake:

1. Didn't understand the question
2. Didn't know the pattern
3. Logic mistake
4. Coding/syntax mistake
5. Edge case missed
6. Time management issue

This classification is extremely important.

Suppose you solve only 4 out of 6 questions.

Don’t simply say:

“I am bad at coding.”

Instead, analyze:

2 questions → Didn't know pattern
1 question → Syntax error
1 question → Correct
1 question → Edge case missed
1 question → Ran out of time

Now you know exactly what to fix.


Day 9 — Full Mock Test

This is your final serious practice day.

Take a complete mock test.

Replicate the exam environment as closely as possible.

After the test, analyze:

Coding

  • Which topics caused problems?
  • Which questions consumed too much time?
  • Did you understand the input/output format?
  • Did you handle edge cases?

Aptitude

  • Which topics were slow?
  • Which formulas did you forget?

Reasoning

  • Did you spend too much time on one puzzle?

Verbal

  • Were errors caused by vocabulary or grammar?

Your goal is not just to get a score.

Your goal is to answer:

“What should I revise tomorrow?”


Day 10 — Final Revision

Don’t learn a completely new topic on Day 10.

Revise.

Your final checklist should include:

Coding

✓ Number manipulation
✓ String manipulation
✓ Arrays
✓ Frequency counting
✓ Searching
✓ Sorting
✓ Matrix basics
✓ Two pointers
✓ Sliding window
✓ Kadane
✓ Stack basics
✓ Linked list basics
✓ Tree traversal basics

Quantitative Aptitude

✓ Percentages
✓ Ratio
✓ Average
✓ Profit & Loss
✓ SI & CI
✓ Time & Work
✓ Time-Speed-Distance
✓ HCF & LCM
✓ Number System
✓ Probability
✓ Permutation & Combination

Reasoning

✓ Number series
✓ Coding-decoding
✓ Blood relations
✓ Directions
✓ Seating arrangement
✓ Syllogism

Verbal

✓ Grammar
✓ Error detection
✓ Sentence correction
✓ Vocabulary
✓ Para jumbles
✓ Reading comprehension

The Most Important Coding Cheat Sheet

If you remember nothing else, remember these patterns.

Number

while n > 0:
digit = n % 10
n //= 10

Frequency

freq[x] = freq.get(x, 0) + 1

Two Pointer

left = 0
right = len(arr) - 1
while left < right:
...

Binary Search

left = 0
right = len(arr) - 1
while left <= right:
mid = (left + right) // 2

Sliding Window

for i in range(k, n):
# add new
# remove old

Kadane

current = max(x, current + x)
best = max(best, current)

These patterns are more valuable than memorizing dozens of isolated solutions.


What You Should NOT Do in These 10 Days

Don’t solve random LeetCode Hard problems

Your goal is not to impress yourself with difficulty.

Your goal is to maximize your exam score.


Don’t spend three days on Trees

Trees are important for general DSA interviews.

But if your exam is in 10 days and your fundamentals are weak, spending hours on advanced tree problems is unlikely to be the best use of your time.


Don’t ignore aptitude

A common mistake is to prepare only coding.

TCS NQT is not just a coding contest.

Your overall performance depends on multiple sections.


Don’t memorize code without understanding patterns

If you memorize:

Question A → Solution A
Question B → Solution B
Question C → Solution C

you may struggle when the question changes slightly.

Instead learn:

Question
Identify Pattern
Choose Data Structure
Write Logic
Test Edge Cases

Your 10-Day Priority Pyramid

If you are extremely short on time, use this order:

                 ┌───────────────┐
                 │   PYQ MOCKS   │
                 └───────┬───────┘
                         │
                ┌────────▼────────┐
                │ Arrays + Strings │
                └────────┬────────┘
                         │
                ┌────────▼────────┐
                │ Number Problems │
                └────────┬────────┘
                         │
                ┌────────▼────────┐
                │ Hashing + Search│
                └────────┬────────┘
                         │
                ┌────────▼────────┐
                │ Sorting + Matrix│
                └────────┬────────┘
                         │
                ┌────────▼────────┐
                │ DSA Fundamentals│
                └─────────────────┘

Final Advice

Ten days is not enough to master every algorithm and data structure.

But ten days is enough to become significantly better prepared if you prioritize correctly.

Your strategy should be:

Learn fundamentals → Recognize patterns → Solve PYQs → Practice under time pressure → Analyze mistakes → Revise weak areas.

The biggest mistake is trying to cover everything.

The better strategy is to become extremely comfortable with the problems that are most likely to reward your preparation.

If you can confidently solve:

  • Number manipulation
  • String manipulation
  • Arrays
  • Frequency problems
  • Searching
  • Sorting
  • Basic matrix problems
  • Common hashing patterns
  • Basic two-pointer problems

and simultaneously prepare the major aptitude topics, you will have a much stronger foundation for your TCS NQT attempt.

The objective isn’t to know everything.

The objective is to know the right things well enough to solve them under pressure.

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