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Solution: First Unique Character in a String

Understand how to identify the first unique character in a string by tracking character frequencies with a hash map. This lesson guides you through solving the problem efficiently with O(n) time and constant space complexity, enabling you to apply frequency analysis 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 ...