字符串：翻转单词顺序列 考察知识迁移能力

 1 class Solution {
 2 public://思路为先翻转整个字符串，再翻转每一个单词
 3     void  ReverseWord(string &str, int start, int end){//传引用！！！！不能传值，致命错误！！
 4         while(start < end){
 5             swap(str[start++], str[end--]);
 6         }
 7     }
 8     string ReverseSentence(string str) {
 9         ReverseWord(str,0,str.size()-1);
10         int i = 0;
11         int start = 0;
12         int end = 0;
13         while(i < str.size()){
14             while(str[i] == ‘ ‘ && i < str.size()){
15                 i++;
16             }
17             end = start = i;
18             while(str[i] != ‘ ‘ && i < str.size()){
19                 i++;
20                 end++;
21             }
22             ReverseWord(str, start, end-1)；//end -1很重眼
23         }
24         return str;
25     }
26 };