Package g0101_0200.s0151_reverse_words_in_a_string

Class Solution

  • public class Solution
extends Object
    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.

    Example 4:

    Input: s = " Bob Loves Alice "

    Output: “Alice Loves Bob”

    Example 5:

    Input: s = “Alice does not even like bob”

    Output: “bob like even not does Alice”

    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?

    • Constructor Detail

      • Solution

        public Solution()

    • Method Detail