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Solution: First Unique Character in a String

Explore how to identify the first unique character in a string by efficiently tracking character occurrences with a hash map. This lesson teaches you to implement a solution with O(n) time complexity and constant space, helping you master character counting patterns useful in coding interviews.

Statement

For a given string of characters, s, your task is to find the first non-repeating character and return its index. Return 1-1 if there’s no unique character in the given string.

Constraints:

  • 11 \leq s.length ...