Interview prep for software engineers

Crack the loop, not just the problem.

Java, SQL and OOP interview questions with clear answers, plus pattern-based DSA. Full solutions, clear reasoning, written for people who want the offer.

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two_pointers.py

# Pattern: two pointers on a sorted array
def pair_sum(nums, target):
    lo, hi = 0, len(nums) - 1
    while lo < hi:
        s = nums[lo] + nums[hi]
        if s == target:
            return lo, hi
        if s < target: lo += 1
        else: hi -= 1
    return None   # O(n) time, O(1) space

Four tracks, one place

Pick the track that matches the interview you are preparing for.

Coding & DSA

Data structures and algorithms, by pattern

Learn the ideas behind most coding questions, then practice them with worked problems.

Hash map lookup Two pointers Sliding window Binary search

Explore DSA patterns

Core CS

Theory questions and software design

Short, clear answers on Java, SQL and OOP, plus design patterns such as Singleton and Factory.

Java SQL and DBMS OOP Design patterns

Browse Core CS

AI & ML

AI, machine learning and LLMs

Search and reasoning, regression and neural networks, then GenAI and LLMs, built up step by step.

AI Machine learning GenAI & LLMs

Explore AI & ML

System design

Design systems that scale

Step-by-step walkthroughs, from requirements to scaling.

Coming soon

Start with a path

Not sure where to begin? Follow the steps in order.

Roadmap

Fresher interview path

1Core Java and OOP
2Strings and collections
3SQL and DBMS basics
4Cheat sheets and mock questions

View the path → Roadmap

Coding interview path

1Hash maps and two pointers
2Sliding window and prefix sums
3Binary search
4Practice sets and review

View the path →

Problem of the week

Median of Two Sorted Arrays

Find the middle value of two sorted arrays in O(log min(m, n)), using a binary search on where to cut.

HardBinary searchJava

Try the problem

Solution.java

public double findMedianSortedArrays(int[] a, int[] b) {
    // find the median in O(log min(m, n))
    return 0.0;
}

Prep that respects your time

01

Patterns over problems

One idea unlocks dozens of questions. We teach the idea first, then the problems.

02

Full solutions on the page

Code, reasoning and trade-offs in the article itself. No hunting through repos.

03

Practice built in

Every pattern ends with worked problems, tested solutions and an original practice question.

Built for people preparing for software interviews

College students

Placement-season prep with plain-language explanations and a clear order to follow.

Self-taught developers

Fill the gaps a degree would have covered, in a sensible order.

Working engineers

Refresh the patterns behind coding rounds without wading through hundreds of problems.