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    OPTIM · OPTIM-001·MID·par 75s·1,777 plays

    Lightning-fast array dedup

    Given an unsorted list of integers, return the two indices that sum to the target. Linear time. No sort tricks.

    MIDSprint · par 75sElo upside · +8 to +16 (top +22)

    Contract

    solve(input: any) → any

    Return the indices, not the values. Order matters.

    Visible tests

    • in: [2, 7, 11, 15], target: 9
      → [0, 1]
    • in: [3, 2, 4], target: 6
      → [1, 2]
    • in: [3, 3], target: 6
      → [0, 1]

    + 7 hidden tests fire on submit

    Step in

    Current Codigami · 1:42 by @reverie

    Your best · 1:58

    Break it for +12 Elo. Fall short for −3.

    Same problem. Two ways to play. Both rank on the same Elo.

    Solve as a coder →Coach the engine (Vibe) →
    Correctness · 50%Speed · 35%Efficiency · 15%

    What this trial is

    Given an unsorted list of integers, return the two indices that sum to the target. Linear time. No sort tricks.

    Sprint trial — par 75s. Fast turnover, dense leaderboard, narrow margins.

    Elo upside if you nail it

    Solid run

    +8 to +16

    Top run

    +22

    Medal line

    silver

    Where most players live. A clean MARK + ROOM here moves the needle every week.

    Solo Elo · MARK ÷ 100 vs field 2100, K-32. Codesport duel wins multiply by ×1.25, losses by ×0.40.

    OPTIM-001 · authored by @house

    Trial leaderboard · OPTIM-001

    Best runs on this trial.

    Composite = MARK · 60% + ROOM · 40%. Top 15% earn Bronze, top 5% Silver, top 1% Gold.

    #
    Handle
    Engine
    Time
    MARK
    ROOM
    Composite
    1
    @reveriemedal
    Opus 4.6
    1:03
    97
    96
    97
    2
    @vex.iomedal
    GPT-5
    0:49
    97
    89
    94
    3
    @ostara
    Gemini 2.5 Pro
    0:35
    97
    89
    93
    4
    @kaz
    Sonnet 4.6
    1:18
    97
    89
    93
    5
    @lumen
    DeepSeek V4
    1:04
    97
    89
    93
    6
    @bram
    Grok 4
    0:50
    91
    89
    89
    7
    @cinder
    Opus 4.6
    1:33
    91
    89
    88
    8
    @halcyon
    GPT-5
    1:19
    91
    89
    88
    9
    @marrow
    Gemini 2.5 Pro
    1:05
    91
    82
    85
    10
    @nyx
    Sonnet 4.6
    1:48
    91
    82
    85

    Top 15% on this trial earns Bronze; top 5% Silver; top 1% Gold. Trial trophies are per-trial visual rewards; the Elo ladder (Demi Coder → Master Coder) is the credential.

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