1 #include "_000库函数.h"
 2
 3
 4 //一开始不知道从何下手
 5 //感觉是用栈，所以用vector来代替栈
 6
 7 class Solution {
 8 public:
 9     string simplifyPath(string path) {
10         vector<string>v;
11         string s = "";//用来记录临时路径
12         int n = 0;//记录‘.’的个数
13         for (int i = 0; i < path.size(); ++i) {
14             if (path[i] == '.')
15                 ++n;
16             else if (path[i] != '/') {//记录次级目录
17                 s.insert(s.end(), n, '.');//防止有些目录名是以.开头！！
18                 n = 0;
19                 s += path[i];
20             }
21             else {//path[i] == '/'
22                 if (n > 2)
23                     s.insert(s.end(), n, '.');
24                 else if (n == 2 && !v.empty())//确保不是在根目录
25                     v.pop_back();// 跳到上一级
26
27                 n = 0;
28                 if (s.size() > 0)
29                     v.push_back(s);
30                 s = "";
31             }
32
33         }
34         if (n > 2)
35             s.insert(s.end(), n, '.');
36         else if (n == 2 && !v.empty())//确保不是在根目录
37             v.pop_back();// 跳到上一级
38         if (s.size() > 0)
39             v.push_back(s);
40         s = "";
41         for (int i = 0; i < v.size(); ++i)//之所以从1开始，是去除根目录的‘/’
42             s = s + "/" + v[i];
43         if (!s.empty())return s;
44         return "/";
45     }
46 };
47
48 //C++中有专门处理字符串的机制，我们可以使用stringstream来分隔字符串，
49 //然后对每一段分别处理，思路和上面的方法相似，参见代码如下：
50 //
51
52 class Solution {
53 public:
54     string simplifyPath(string path) {
55         string res, t;
56         stringstream ss(path);
57         vector<string> v;
58         while (getline(ss, t, '/')) {
59             if (t == "" || t == ".") continue;
60             if (t == ".." && !v.empty()) v.pop_back();
61             else if (t != "..") v.push_back(t);
62         }
63         for (string s : v) res += "/" + s;
64         return res.empty() ? "/" : res;
65     }
66 };
67
68
69
70 void T071() {
71     Solution s;
72     string str;
73     str = "/home/";
74     cout << "输入：" << str << endl << "输出：" << s.simplifyPath(str) << endl;
75     str = "/../";
76     cout << "输入：" << str << endl << "输出：" << s.simplifyPath(str) << endl;
77     str = "/home//foo/";
78     cout << "输入：" << str << endl << "输出：" << s.simplifyPath(str) << endl;
79     str = "/a/./b/../../c/";
80     cout << "输入：" << str << endl << "输出：" << s.simplifyPath(str) << endl;
81     str = "/a/../../b/../c//.//";
82     cout << "输入：" << str << endl << "输出：" << s.simplifyPath(str) << endl;
83     str = "/a//bc/d//././/..";
84     cout << "输入：" << str << endl << "输出：" << s.simplifyPath(str) << endl;
85     str = "/...";
86     cout << "输入：" << str << endl << "输出：" << s.simplifyPath(str) << endl;
87
88 }