Coding interview problems

3,736 problems: 937 Easy, 1,914 Medium, 885 Hard. Each runs against hidden tests, in 13 languages; database problems in SQL. Free for members.

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Problems 601–700 of 3,736

601. Sum of Prefix Match Scores Hard · String, Hash Table, Binary Search
602. Repeats Inside Repeats Hard · String, Hash Table, Dynamic Programming
603. Exact-K Occurrence Subarrays Medium · Array, Hash Table, Sliding Window
604. Smallest Missing Value per Subtree Hard · Tree, Hash Table, Depth-First Search
605. Valid Palindrome Easy · Two Pointers, String · Asked at Meta, Microsoft, Amazon · 100% accepted
606. Is Subsequence Easy · Two Pointers, String, Dynamic Programming · Asked at Google, Amazon
607. Two Sum II - Input Array Is Sorted Medium · Array, Two Pointers, Binary Search · Asked at Amazon, Google
608. Container With Most Water Medium · Array, Two Pointers, Greedy · Asked at Amazon, Google, Meta
609. 3Sum Medium · Array, Two Pointers, Sorting · Asked at Amazon, Meta, Google
610. Trapping Rain Water Hard · Array, Two Pointers, Dynamic Programming, Monotonic Stack · Asked at Amazon, Google, Goldman Sachs
611. Find K-th Smallest Pair Distance Hard · Array, Two Pointers, Binary Search, Sorting · Asked at Google
612. Reverse the Shelf Labels Easy · Array, String, Two Pointers
613. Nearest Triple Sum Medium · Array, Two Pointers, Sorting
614. Four-Way Split to a Target Medium · Array, Two Pointers, Sorting
615. Count Triples Under a Cap Medium · Array, Two Pointers, Sorting
616. Mirror Ticket Number Easy · Math, Two Pointers
617. Park the Empty Crates Easy · Array, Two Pointers
618. Strip the Banned Code Easy · Array, Two Pointers
619. Distinct Sorted Readings Easy · Array, Two Pointers
620. Fewest Swaps to Front-Load Evens Easy · Array, Two Pointers, Greedy
621. Shared Badges of Two Teams Easy · Array, Two Pointers, Sorting
622. Union of Sorted Catalogs Easy · Array, Two Pointers
623. Cheapest Dial Turns to a Mirror Easy · String, Two Pointers, Greedy
624. Count Affordable Pairs Easy · Array, Two Pointers, Sorting
625. Flip a Section of the Playlist Easy · Array, Two Pointers
626. Word-Level Mirror Sentence Easy · String, Two Pointers
627. Find the Lost Parcel Easy · Array, Two Pointers
628. Richest Walk Across Two Trails Hard · Array, Two Pointers, Dynamic Programming, Greedy
629. Best Pair Under the Limit Easy · Array, Two Pointers, Sorting
630. Distinct Magnitudes in a Sorted List Easy · Array, Two Pointers
631. Present in All Three Ledgers Easy · Array, Two Pointers
632. Closest Pair Sum to a Target Easy · Array, Two Pointers, Sorting
633. Tug-of-War Tally Easy · Array, Two Pointers, Simulation
634. K-th of Two Sorted Queues Easy · Array, Two Pointers
635. Longest Mirrored Prefix Easy · String, Two Pointers
636. One Smudge Allowed Easy · String, Two Pointers, Greedy
637. Balanced Seesaw Row Easy · Array, Two Pointers
638. Best Combo Under Budget Easy · Array, Two Pointers
639. Nearest Gap Between Two Words Easy · Array, String, Two Pointers
640. Interleave the Deck Halves Easy · Array, Two Pointers
641. Mirror Bracket String Easy · String, Two Pointers
642. Match Buddies Within Tolerance Easy · Array, Two Pointers, Greedy, Sorting
643. Upside-Down Number Easy · String, Two Pointers, Hash Table
644. Double the Zeros Easy · Array, Two Pointers
645. Reverse in Alternate Blocks Easy · String, Two Pointers
646. Digit-Square Loop Easy · Math, Two Pointers, Hash Table
647. Tightest k Scores Easy · Array, Two Pointers, Sorting
648. Count Distinct Midpoints Easy · Array, Two Pointers, Sorting, Hash Table
649. Two Swapped Entries Easy · Array, Two Pointers, Sorting
650. Count Cross Overtakes Easy · Array, Two Pointers, Sorting
651. Summarize Ticket Runs Easy · Array, Two Pointers
652. Erase by Mirror Pieces Easy · String, Two Pointers
653. Cheapest Paired Workload Easy · Array, Sorting, Greedy, Two Pointers
654. Count Buildable Triangles Medium · Array, Two Pointers, Sorting, Greedy
655. Fewest Rafts Across Medium · Array, Two Pointers, Sorting, Greedy
656. Lightest Heaviest Pair Medium · Array, Two Pointers, Sorting, Greedy
657. Distinct Gap Pairs Medium · Array, Two Pointers, Sorting, Hash Table
658. Keep at Most Two Copies Medium · Array, Two Pointers
659. Overlap of Two Shift Lists Medium · Array, Two Pointers, Intervals
660. Subtract Blocked Intervals Medium · Array, Two Pointers, Intervals
661. Longest Ridge in the Terrain Medium · Array, Two Pointers
662. Longest Word by Erasing Medium · String, Two Pointers, Sorting
663. Count Hidden Words Medium · String, Two Pointers, Hash Table
664. Stretched Shouts Medium · String, Two Pointers
665. Trim Matching Ends Medium · String, Two Pointers
666. Slide the Robots Medium · String, Two Pointers
667. Repeated Ticket in a Range Medium · Array, Two Pointers, Bit Manipulation
668. One-Way Loop in a Ring Medium · Array, Two Pointers, Hash Table
669. Pair Across Two Search Trees Medium · Tree, Binary Search Tree, Two Pointers, Depth-First Search
670. Fewest Merges to a Mirror Medium · Array, Two Pointers, Greedy
671. Mirror From Two Strings Medium · String, Two Pointers
672. Alternate Signs in Order Medium · Array, Two Pointers
673. Spend or Cash Cards Medium · Array, Two Pointers, Sorting, Greedy
674. Shortest Cut to Sorted Medium · Array, Two Pointers, Binary Search
675. Most Target Pairs Removed Medium · Array, Two Pointers, Sorting, Hash Table
676. Balanced Skill Duos Medium · Array, Two Pointers, Sorting
677. Pair Climbers With Ropes Medium · Array, Two Pointers, Sorting, Greedy
678. Widest Valid Span of Two Lists Medium · Array, Two Pointers, Binary Search
679. Earliest Common Meeting Slot Medium · Array, Two Pointers, Sorting, Intervals
680. Sorted Parabola Values Medium · Array, Two Pointers, Math, Sorting
681. Roomiest Seat on the Bench Medium · Array, Two Pointers
682. Square Equals Product Triples Medium · Array, Two Pointers, Math, Hash Table
683. Longest Upward Reach Medium · Array, Two Pointers, Stack, Monotonic Stack
684. Best-Paying Gigs Medium · Array, Two Pointers, Sorting, Greedy
685. Home Advantage Pairs Medium · Array, Two Pointers, Sorting
686. Spread After Three Changes Medium · Array, Sorting, Greedy
687. Painting From Both Ends Medium · Array, Two Pointers, Simulation
688. Closest Across Three Lists Medium · Array, Two Pointers, Sorting
689. Triples in a Sum Range Medium · Array, Two Pointers, Sorting
690. Total Gap Between Two Lists Medium · Array, Two Pointers, Prefix Sum, Sorting
691. Narrowest Band After Shifts Medium · Array, Sorting, Greedy, Math
692. Most Removable Letters Medium · String, Two Pointers, Binary Search
693. Longest Climb With One Skip Medium · Array, Two Pointers, Dynamic Programming
694. Symmetric Swaps to Sort Easy · Array, Two Pointers, Dynamic Programming, Greedy
695. Last Seat on the Shuttle Medium · Array, Two Pointers, Sorting, Simulation
696. Count Overlapping Booking Pairs Medium · Array, Two Pointers, Sorting, Intervals
697. Most Equal After Raises Medium · Array, Two Pointers, Sorting, Sliding Window
698. Most Points on an Arc Medium · Array, Two Pointers, Sorting, Sliding Window
699. Extract the Pattern Repeatedly Easy · String, Two Pointers, Greedy
700. Longest Run That Hides in Another Medium · String, Two Pointers, Dynamic Programming