Algorithms & recursion in Java: interview exercises

Algorithms & recursion in Java: 6 test-checked interview exercises (Binary search, Two sum), each beside a worked example, with tests as you go. Free.

1. Binary search
2. Two sum
3. Merge overlapping intervals
4. Memoized recursion
5. All permutations
6. Count the islands

Each exercise pairs a worked example with a twin problem to solve in a real editor; the tests run the moment you do. Progress is saved in your browser, and in your account if you sign in.

More Java topics

• Strings
• Collections
• Streams & lambdas
• Records, classes & interfaces
• Generics & Optional
• Exceptions & validation
• Modern Java

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