Reverse Words in a String

Problem Statement

Given a string, reverse the order of the words. Words are separated by one or more spaces, and the result should not contain leading or trailing spaces, with exactly one space between words. This is an easy-level problem testing string manipulation skills.

Example

Input: s = " hello world "

Output: "world hello" (reversed words with single spaces)

Input: s = "the sky is blue"

Output: "blue is sky the"

Code

public class Solution {
    public String reverseWords(String s) {
        String[] words = s.trim().split("\\s+");
        StringBuilder result = new StringBuilder();
        
        for (int i = words.length - 1; i >= 0; i--) {
            result.append(words[i]);
            if (i > 0) result.append(" ");
        }
        return result.toString();
    }
}
            

def reverse_words(s):
    words = s.strip().split()
    return " ".join(words[::-1])

# Example usage
print(reverse_words("  hello   world  "))  # "world hello"
print(reverse_words("the sky is blue"))    # "blue is sky the"
            

function reverseWords(s) {
    let words = s.trim().split(/\s+/);
    return words.reverse().join(" ");
}

// Example usage
console.log(reverseWords("  hello   world  ")); // "world hello"
console.log(reverseWords("the sky is blue"));   // "blue is sky the"
            

Explanation

• Trim the string to remove leading and trailing spaces.
• Split the string into words, handling multiple spaces appropriately.
• Reverse the array of words (either manually or using built-in methods).
• Join the words back together with a single space between them.
• Return the resulting string.

Note