Problem Statement

Given a character array s, return the updated array after reversing the order of words in the array.

A word is defined as a sequence of non-space characters, and the words are separated by one space character. The input array does not contain any leading or trailing spaces, and the words are always separated by a single space.

Note: Your code must solve the problem without using any extra space.

Examples

• Example 1:

  • Input: ["h","e","l","l","o"," ","w","o","r","l","d"]
  • Expected Output: ["w","o","r","l","d"," ","h","e","l","l","o"]
  • Justification: The original string is "hello world". Reversing the words gives "world hello".

• Example 2:

  • Input: ["m","o","r","n","i","n","g"," ","s","k","y"," ","i","s"," ","b","r","i","g","h","t"]
  • Expected Output: ["b","r","i","g","h","t"," ","i","s"," ","s","k","y"," ","m","o","r","n","i","n","g"]
  • Justification: The original string is "morning sky is bright". Reversing the words gives "bright is sky morning".

• Example 3:

  • Input: ["a","l","o","n","e"]
  • Expected Output: ["a","l","o","n","e"]
  • Justification: There's only one word "alone", so the reverse is the same as the original.

Try it yourself

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