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CoursesSearch & Priority Patterns

Binary Search

Lessons
9
Exercises
56
Minutes
56
  1. 1

    Halve the Search Space

    Spot the problems where one comparison can safely throw away half the candidates.

    Multiple choiceTap
    5 exercises
    4 min
  2. 2

    Binary Search

    Keep the target trapped in [lo, hi] until you find it — or the window empties.

    Complete codeDebugMultiple choiceTrace
    6 exercises
    6 min
  3. 3

    Search Insert Position

    When the loop misses, lo is already standing on the insertion point.

    Complete codeDebugMultiple choiceTrace
    6 exercises
    6 min
  4. 4

    First Bad Version

    Binary search a yes/no boundary: keep every 'bad' candidate in range until the pointers pinch the first one.

    Complete codeDebugMultiple choiceTrace
    6 exercises
    6 min
  5. 5

    First and Last Position

    On equal, don't stop — bias the search left or right so duplicates can't hide the true boundary.

    Complete codeMultiple choiceTrace
    6 exercises
    6 min
  6. 6

    Minimum in Rotated Array

    Compare mid against the RIGHT end — that one comparison always reveals which side hides the drop.

    Complete codeDebugMultiple choiceTrace
    6 exercises
    6 min
  7. 7

    Binary Search CheckpointCheckpoint

    No new concepts — combine the island's variants: picking exact-match vs boundary vs biased searches, the containment invariant, safe mid, and loop progress.

    DebugCode orderFill blankMultiple choiceTrace
    6 exercises
    6 min
  8. 8

    Binary Search ReviewReview

    Mixed recap of the island: when halving applies, exact-match vs boundary moves, the insertion point, biased searches, rotated minimums, and why log n is so fast.

    Complete codeMultiple choiceTapTrace
    7 exercises
    6 min
  9. 9

    Boss: Search in Rotated ArrayBoss

    The island's final test: binary search an array whose order is bent. At every mid exactly one half is properly sorted — identify it, range-test the target against it, and discard half the array anyway.

    Complete codeCode orderMultiple choiceTrace
    8 exercises
    10 min
AlgoFox Pro

Search & Priority Patterns is part of AlgoFox Pro

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