Runtime Lab

Task

Write nonRepeat(str) to return the last non-repeating character, or an empty string if none exists.

Input: "paper"
Output: "r"

Last Non-Repeating Character

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Your JS

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Name

Note: Your code runs on the server worker. Define nonRepeat(str) and avoid infinite loops.

Runtimes

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Test	Status	Avg ms

Highscore (fastest avg per call)

Passing solutions with stored code

Rank	Name	Entry ID	Avg ms	Status	Logged
1	K2	17c40b60f7b98a3f3ce0296ca87cc1f24359ee32d2e90f80c740de11dd38cfab	0.0044	Passed (31/31)	1/10/2026, 12:28:44 AM

Stored on the server per task.