Reverse Words in a String

Given an input string, reverse the string word by word.

For example,
Given s = "the sky is blue",
return "blue is sky the".

Clarification:

• What constitutes a word?
  A sequence of non-space characters constitutes a word.
• Could the input string contain leading or trailing spaces?
  Yes. However, your reversed string should not contain leading or trailing spaces.
• How about multiple spaces between two words?
  Reduce them to a single space in the reversed string.

 

#include "stdafx.h"
#include <string>
#include <iostream>
using namespace std;


class Solution{
public:
    void reverseWords(string &s)
    {
        string revese, tmp;
        int k = 0;
        while (s[k] == ' ')    //ignore the leading spaces
        {
            k++;
        }

        for (int i = k; i < s.size();)
        {
            if (s[i] != ' ')
            {
                tmp += s[i++];
            }
            else 
            {
                while (s[i] == ' ') // reduce the spaces to a single space
                    i++;
                if (i == s.size())
                    break;
                revese = " " + tmp + revese;
                tmp = "";
            }
        }
        s = tmp + revese;
    };
};

int _tmain(int argc, _TCHAR* argv[])
{
    Solution *sln = new Solution();
    string s = "  hello dd  ";
    sln->reverseWords(s);
    cout << s << endl;

    return 0;
}