LeetCode——Reverse Words in a String

题目：

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

For example,

Given s = "

the sky is blue

",

return "

blue is sky the

".

遍历字符串，把字符串中的单词分割并保存到vector中，然后新建一个字符串，从后往前获取单词，依次往字符串中追加单词。

#include <iostream>
#include <string>
#include <vector>
using namespace std;

void reverseWords(string &s) {  	
        vector<string> vec;
        string rs;
        int start=0;
	int end=0;
	string temp;
	for(int i=0;i<s.size();i++)
	{
		if(s[i]==' ')
		{
			if(i-start>0)
			{
				temp=s.substr(start,i-start);
				vec.push_back(temp);
			}
			start=i+1;
			}
			else if(i==s.size()-1)
			{
				temp=s.substr(start,i-start+1);
				vec.push_back(temp);
			}
		}
		temp="";
  		for(int i=vec.size()-1;i>=0;i--)
		{
		        temp.append(vec[i]);
			if(i!=0)
			{
				temp.append(" ");
			}
		}
		
		s=temp;	
    }  
	

	void main()
	{
		string s="   seasons     in the sun   ";
		reverseWords(s);
		cout<<s<<endl;
	}