🎯 A complete, well-organized collection of InterviewBit solutions in Java

📚 450+ Problems • 🧠 Optimal Approaches • 🧪 Fully Tested • 📖 Explained

     

InterviewBit Java Solutions is a curated, meticulously organized repository of 450+ InterviewBit problems solved in Java — with clean code, optimal complexity, and clear explanations.

Every solution is written with interview-readiness in mind: readable, well-commented, and following Java best practices. Perfect for cracking FAANG-style interviews or leveling up your problem-solving skills.

💡 Structure: Problems are grouped by topic (Arrays, Trees, DP, Graphs...) and difficulty (Easy / Medium / Hard), so you can target specific areas quickly.

/**
 * Problem: Two Sum
 * Difficulty: Medium
 * Approach: HashMap for O(1) lookup of complements
 *
 * Time:  O(n)
 * Space: O(n)
 */
public int[] twoSum(int[] nums, int target) {
    Map<Integer, Integer> seen = new HashMap<>();
    for (int i = 0; i < nums.length; i++) {
        int complement = target - nums[i];
        if (seen.containsKey(complement)) {
            return new int[] { seen.get(complement), i };
        }
        seen.put(nums[i], i);
    }
    throw new IllegalArgumentException("No solution");
}

☕ interviewbit-java-solutions/
├── 📂 arrays/
│   ├── easy/
│   ├── medium/
│   └── hard/
├── 📂 strings/
├── 📂 linked-lists/
├── 📂 trees/
├── 📂 graphs/
├── 📂 dynamic-programming/
├── 📂 backtracking/
├── 📂 math-and-bits/
├── 🧪 tests/                  # JUnit 5 test cases
└── 📖 docs/                   # Approach notes & complexity tables

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Distributed under the MIT License. See LICENSE for details.

Note: This repository is a community-driven educational resource. All problem statements are property of InterviewBit. Solutions are shared for learning purposes only.

☕ Made with 💙 by the InterviewBit Java Community

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