This Hudson River Trading coding question tests hash-based counting for pairs that become equivalent after a digit-reversal transform. It is useful for practicing canonicalization, duplicate accounting, and careful handling of numeric string edge cases.
Company: Hudson River Trading
Role: Software Engineer
Category: Coding & Algorithms
Difficulty: medium
Interview Round: Technical Screen
Overview: This Hudson River Trading coding question tests hash-based counting for pairs that become equivalent after a digit-reversal transform. It is useful for practicing canonicalization, duplicate accounting, and careful handling of numeric string edge cases.
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