Function reverseWords

reverse_words_in_a_string_151/solution.go:6–33

Note: solution using a single string with which tokens are prepended into.

(s string)

// Note: solution using a single string with which tokens are prepended into.
func reverseWords(s string) string {
	s = strings.Trim(s, " ")

	sFinal := ""
	start := 0
	finish := 0
	for finish < len(s) {
		if string(s[finish]) == " " {
			// prepend the token found into the final string
			// this is slow, "don't concat strings in a loop"
			sFinal = s[start:finish] + " " + sFinal

			// clear whitespace in between tokens for next start
			for string(s[finish]) == " " {
				finish++
			}

			start = finish
		} else {
			finish++
		}
	}

	// Prepend final token as finish stopped at the end of s
	sFinal = s[start:finish] + " " + sFinal

	return strings.TrimSuffix(sFinal, " ")
}

// Note: First, correct, and optimal runtime solution using an array
// for tokens and reversing the array.