ReverseWordsInAString.ts

// Source : https://leetcode.com/problems/reverse-words-in-a-string/
// Author : francisco
// Date   : 2023-12-19

/*****************************************************************************************************
 *
 * Given an input string s, reverse the order of the words.
 *
 * A word is defined as a sequence of non-space characters. The words in s will be separated by at
 * least one space.
 *
 * Return a string of the words in reverse order concatenated by a single space.
 *
 * Note that s may contain leading or trailing spaces or multiple spaces between two words. The
 * returned string should only have a single space separating the words. Do not include any extra
 * spaces.
 *
 * Example 1:
 *
 * Input: s = "the sky is blue"
 * Output: "blue is sky the"
 *
 * Example 2:
 *
 * Input: s = "  hello world  "
 * Output: "world hello"
 * Explanation: Your reversed string should not contain leading or trailing spaces.
 *
 * Example 3:
 *
 * Input: s = "a good   example"
 * Output: "example good a"
 * Explanation: You need to reduce multiple spaces between two words to a single space in the reversed
 * string.
 *
 * Constraints:
 *
 * 	1 <= s.length <= 10^4
 * 	s contains English letters (upper-case and lower-case), digits, and spaces ' '.
 * 	There is at least one word in s.
 *
 * Follow-up: If the string data type is mutable in your language, can you solve it in-place with O(1)
 * extra space?
 ******************************************************************************************************/

/**
 * @param {string} s
 * @returns {string}

 * given an input string, s, return a string of the words in reverse order concatenated by a single space
 * NOTE: a word is defined as a sequence of non space characters
 * ASSUME: the words in s will be separated by at least one space

 * Stub:
 function reverseWords(s: string): string {return ""}

 * Tests:
 * I: s = "the sky is blue" -> O: "blue is sky the"
 * I: s = "  hello world  " -> O: "world hello"
 * I: s = "a good   example" -> O: "example good a"

 * Time Complexity: O(n), where n is the length of s
 * Space Complexity O(m), where m is the number of words

 * Runtime: 41ms (99.18%)
 * Memory: 44.14MB (93.63%)
 */
export function reverseWords(s: string): string {
  return s.trim().split(" ").filter(Boolean).reverse().join(" ");
}