Description
Given a string s, reverse the order of characters in each word within a sentence while still preserving whitespace and initial word order.
Example 1:
Input: s = "Let's take LeetCode contest"
Output: "s'teL ekat edoCteeL tsetnoc"
Example 2:
Input: s = "Mr Ding"
Output: "rM gniD"
Constraints:
1 <= s.length <= 5 * 104s contains printable ASCII characters.s does not contain any leading or trailing spaces.- There is at least one word in
s.
- All the words in
s are separated by a single space.
Solutions
Solution 1: Simulation
We can split the string s into an array of words words by spaces, then reverse each word and concatenate them back into a string.
The time complexity is O(n), and the space complexity is O(n). Here, n is the length of the string s.
PythonJavaC++GoTypeScriptRustJavaScriptPHP
class Solution:
def reverseWords(self, s: str) -> str:
return " ".join(t[::-1] for t in s.split())(code-box)
class Solution {
public String reverseWords(String s) {
String[] words = s.split(" ");
for (int i = 0; i < words.length; ++i) {
words[i] = new StringBuilder(words[i]).reverse().toString();
}
return String.join(" ", words);
}
}(code-box)
class Solution {
public:
string reverseWords(string s) {
stringstream ss(s);
string t;
string ans;
while (ss >> t) {
reverse(t.begin(), t.end());
ans += t;
ans.push_back(' ');
}
ans.pop_back();
return ans;
}
};(code-box)
func reverseWords(s string) string {
words := strings.Fields(s)
for i, w := range words {
t := []byte(w)
slices.Reverse(t)
words[i] = string(t)
}
return strings.Join(words, " ")
}(code-box)
function reverseWords(s: string): string {
return s
.split(' ')
.map(t => t.split('').reverse().join(''))
.join(' ');
}(code-box)
impl Solution {
pub fn reverse_words(s: String) -> String {
s.split(' ')
.map(|s| s.chars().rev().collect::<String>())
.collect::<Vec<_>>()
.join(" ")
}
}(code-box)
/**
* @param {string} s
* @return {string}
*/
var reverseWords = function (s) {
return s
.split(' ')
.map(t => t.split('').reverse().join(''))
.join(' ');
};(code-box)
class Solution {
/**
* @param String $s
* @return String
*/
function reverseWords($s) {
$words = explode(' ', $s);
foreach ($words as $i => $word) {
$words[$i] = strrev($word);
}
return implode(' ', $words);
}
}(code-box)
