Refresh your DSA knowledge with problems across arrays, strings, trees, graphs, dynamic programming, and more. Compare approaches, explain their complexity, and revisit the problems that challenge you.
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Blind 75 provides a focused collection of data structures and algorithms problems for coding interview revision. It helps you revisit familiar topics, recognise useful approaches, and practise turning an idea into a solution you can explain and implement independently.
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The sheet is organised into 10 topic modules, giving you a clear way to work through different areas of DSA and return to the ones that need more practice.
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Work through arrays, bit manipulation, dynamic programming, graphs, intervals, linked lists, matrices, strings, trees, and heaps. The syllabus also includes binary search on rotated arrays, sliding-window problems, binary search tree questions, and trie operations.
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Practise identifying pairs with Two Sum, ordering dependencies with Course Schedule, combining overlapping intervals, and reasoning about choices in Word Break. Other problems explore linked-list pointers, matrix traversal, tree paths, frequent elements, and the median of a data stream.
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For each question, identify what information you need to keep track of and why your chosen data structure helps. Explain how the approach progresses, when it stops, and what makes the result correct.
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Compare related problems as you revise. A change in the input, constraints, or required output may call for a different approach, even when the question initially looks familiar.
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Blind 75 is suitable for students preparing for placements and developers revising for software engineering interviews. You should be comfortable using one programming language and understand core data structures, recursion, and basic complexity analysis.
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Use your revision sessions to practise explaining an idea before coding, checking assumptions, and responding to follow-up questions. The aim is to understand the reasoning well enough to solve variations and recognise where you need further practice.