Topics
How to dry-run code
Trace any program on paper with a variable table.
Reading company-test pseudocode
Translate exam pseudocode into real logic and predict the output.
Operator traps: ++, %, /, &&, bitwise
Avoid the classic MCQ traps.
Digit problems: reverse, palindrome, Armstrong
Extract digits with % and /.
Prime numbers and the sieve
Check primes efficiently and list primes up to n.
GCD, LCM and number theory basics
Use Euclid's algorithm and modular arithmetic.
Pattern printing
Crack star, number, alphabet and diamond patterns.
Array basics: max, second largest, rotate
Solve the most common array questions.
Frequency, duplicates and missing number
Count with arrays/hash and use sum tricks.
String questions: vowels, reverse words, palindrome
Handle common string tasks and edge cases.
Anagrams and character counting
Compare strings by frequency.
Sorting in coding tests
Use sorting to simplify problems.
Binary search in tests
Use binary search for fast lookups and answers.
Recursion output questions
Predict outputs of recursive functions.
Bit manipulation
Use &, |, ^, << for fast tricks.
Matrix questions: spiral, transpose, rotate
Traverse 2D arrays in tricky orders.
Hashing for coding rounds
Use maps/sets to cut O(n^2) to O(n).
Greedy problems
Pick the locally best choice when it works.
DP basics for tests
Recognise simple DP: stairs, max sum with no adjacent.
Timed online-test problem walkthrough
Solve a full NQT-style problem under time.
Company coding-round problem walkthrough
Handle medium array/string problems.
Input handling and edge cases
Avoid failing hidden test cases.
Full mock walkthrough
Combine skills in a timed mock.