Minimum window substringCodingGiven strings s and t, return the shortest substring of s that contains every character of t, counting repeats, or an empty string if there is none. Grow the window until it…
Last asked May 2026
Character.AI
A recruiter call, a hiring manager screen on past scaling work, a 60-minute live coding screen, then a virtual onsite of four or five rounds (coding, LLM serving and inference, system design for stateful chat, behavioral), plus a founder or CTO talk for senior hires.
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