Reverse the order of the words
A text filter turns a sentence back to front, word by word, without disturbing the words themselves.
- Only the order of the words changes; the letters inside each word stay put.
- Runs of whitespace collapse to one space, and the ends are trimmed.
- Text with no words gives an empty string.
reverseWords(text: string) → string
Go needs a compiler and Drill does not host one yet, so this page is the reference rather than an exercise: the problem, worked examples, and the solution in full. To type it out, the same problem runs in Python.
Where you start
func reverseWords(text string) string {
}Worked examples
| Call | Result |
|---|---|
reverseWords("the quick brown fox") | "fox brown quick the" |
reverseWords(" a b ") | "b a" |
reverseWords("one") | "one" |
reverseWords("") | "" |
Hint
Split on whitespace, reverse the list, join with a single space.
Reference solution in Go
func reverseWords(text string) string {
words := strings.Fields(text)
for i, j := 0, len(words)-1; i < j; i, j = i+1, j-1 {
words[i], words[j] = words[j], words[i]
}
return strings.Join(words, " ")
}