Build topic by topic: start with arrays, strings, and hash maps, then move to linked lists, stacks, queues, trees, graphs, recursion, and dynamic programming. For each topic, revise the concept, solve 20–30 problems, and note the patterns you see instead of memorizing solutions. If your interview is 6–10 weeks away, spend the first half on core topics and the second half on timed practice and mock interviews, because interviewers evaluate how you think, not just whether your code runs.

Restate the problem in your own words, confirm the constraints, and present a brute-force solution before optimizing it. As you improve the solution, name the pattern you are applying — two pointers, sliding window, binary search on answer, dynamic programming — and always close by stating the time and space complexity. Dry-run your final code on one sample input so the interviewer can follow your logic. Rehearsing this exact flow in a mock session is what most candidates do before product company interviews.

Freshers are most frequently tested on array problems (reversal, rotation, Kadane's algorithm), string problems (palindrome, anagram), linked list reversal and cycle detection, stack-based questions, binary search variations, tree traversals, and entry-level dynamic programming like Fibonacci, climbing stairs, and 0/1 knapsack. Learn the pattern behind each answer rather than memorizing code, since interviewers change the story to test real understanding. Mastering around 100–150 such questions comfortably covers what most Indian service-based and product-based companies ask freshers.

Yes, Java is completely acceptable — interviewers assess your logic, not your language. Java is in fact one of the most common first languages among Indian candidates, and many product companies use it in their own codebases. Stick with the language you can write fastest and cleanest; just be fluent with Java collections like HashMap, ArrayList, PriorityQueue, and HashSet, since you will reach for them constantly while coding solutions. Switching to C++ only for interviews usually costs more time than it gains.

Use PDFs for revision and platforms for practice. A compiled PDF of standard questions is handy in the final week before an interview, but real interviewers rarely ask textbook versions — they twist the problem slightly to test depth. So spend roughly 80% of your time actually coding on online judges where you can compile, test, and debug, and convert your own solved problems into personal notes. Reading someone else's PDF without writing code creates false confidence.

GeeksforGeeks is an excellent starting point — its concept explanations and company-wise archives show what firms like Amazon, Microsoft, and Flipkart have actually asked. However, top product companies increasingly frame newer variations, so treat GeeksforGeeks as your foundation and then layer on live problem solving through LeetCode practice and contests on CodeChef or HackerRank. If you can explain your approach aloud and optimize on the spot, that combination is enough for most product company rounds.

Freshers starting from scratch typically need 3–4 months at around 2 hours a day, while working professionals with some coding background usually manage in 2–3 focused months. A common benchmark in India is 150–200 well-understood problems covering all core topics, followed by two weeks of timed contests and mock interviews. Consistency matters more than duration — solving one problem daily beats solving ten problems on a Sunday.

Most Indian aspirants combine two or three: LeetCode for interview-style problems, GeeksforGeeks for concept clarity and company-wise archives, CodeChef and HackerRank for contests and structured tracks, and freeCodeCamp if you want a free guided curriculum. Pick one platform for learning and one for contests rather than hopping across all of them. Mentors who actively compete on these platforms — for example, Santhosh S, a CodeChef gold badge holder who mentors on Topmate — can also point you to the problem types your target companies repeat.

It depends on your discipline and deadline. If you can self-study consistently from free resources, a course adds limited value. It becomes worth paying for when you keep procrastinating, get stuck without guidance, or have an interview lined up within a couple of months and need a structured plan with feedback. Before paying, check whether you get 1:1 doubt clearing and mock interviews, and prefer mentors with a satisfaction guarantee — Santhosh S on Topmate, for instance, offers a 100% refund if a mentee is not satisfied, which lowers the risk of trying a paid session.

Do not jump straight to code. Restate the problem, ask clarifying questions about input size and edge cases, dry-run a small example, and state the simplest brute-force solution first. Then look for a signal — sorted input suggests binary search or two pointers, subarray sums suggest sliding window or prefix sums, and counting/lookups suggest hashing. Optimize step by step, code cleanly, and test with edge cases. Interviewers deliberately pick unfamiliar problems, so a repeatable framework matters more than having memorized 500 solutions.

Paste your resume along with the exact job description and ask ChatGPT to act like a recruiter for that role — requesting ATS keyword matching, stronger action verbs, quantified achievements, and removal of filler lines. Verify every suggestion manually, because AI tends to insert generic phrasing and cannot judge the hiring bar of a specific company or role. For the final version, a human check still adds value; mentors like Santhosh S, who has reviewed many resumes and helped candidates start receiving interview calls after reworking them, offer personalized resume reviews that go beyond what AI catches.

A CV review is when an experienced professional evaluates your CV for format, clarity, relevance, and impact — checking whether achievements are quantified, skills match the roles you are targeting, and the document passes applicant tracking systems. In India, "CV" and "resume" are used interchangeably, so a CV review effectively means a resume review. Freshers benefit the most because they typically copy templates and list responsibilities instead of achievements, which is the most common reason applications get rejected without interview calls.

A blind (anonymized) resume review hides personal details such as your name, photo, gender, age, and sometimes college name, so the document is judged purely on skills, projects, and experience. Many companies now use this method internally to reduce hiring bias, and some mentors review resumes blind to give genuinely unbiased feedback. For you as a candidate, the takeaway is to structure your resume so the achievements and skills sections can stand on their own without leaning on a brand-name college or references.

If you are applying regularly but not getting interview calls, your resume is usually the bottleneck, and a professional resume review service targets exactly that — weak bullet points, missing keywords for the role, and formatting that fails ATS filters. Free feedback from friends or AI tools helps with polish but rarely reflects what recruiters in your specific domain expect. Choose a reviewer who works in the industry and has reviewed resumes in your field; many mentors on Topmate, including Santhosh S, offer this with a satisfaction-based refund policy, so the cost of trying it is low.