151. Reverse Words in a String
Medium
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 <= 104
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?func reverseWords(s string) string {
words := strings.Fields(s)
res := words[len(words)- 1]
for i := len(words)-2; i >= 0; i-- {
res = res + " " + words[i]
}
return res
}