Google Coding Interview Question and Answer #1: First Recurring Character

Find the first recurring character in the given string!

A variation of this problem: find the first NON-recurring character. This variation problem and many others are covered in my Udemy course, 11 Essential Coding Interview Questions: https://www.udemy.com/11-essential-coding-interview-questions/?couponCode=GOOGLE1

(You’ll get a discount through the above link.)

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