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Reverse a String In-Place is a easy coding interview question covering strings, two pointers — the kind asked at FAANG (Facebook/Meta, Apple, Amazon, Netflix, Google) and AI-first companies like Anthropic, OpenAI, and Nvidia.
Reverse a string in-place using a character array. Also implement a follow-up: reverse the words in a sentence while keeping word order reversed.
Example 1: ["h","e","l","l","o"] -> ["o","l","l","e","h"] Example 2: "the sky is blue" -> "blue is sky the"
For the word reversal follow-up, do not use extra space proportional to input length.
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