Simplify Path [LeetCode]

Given an absolute path for a file (Unix-style), simplify it.

For example,
path = "/home/", => "/home"
path = "/a/./b/../../c/", => "/c"

click to show corner cases.

Corner Cases:

 

  • Did you consider the case where path = "/../"?
    In this case, you should return "/".
  • Another corner case is the path might contain multiple slashes '/' together, such as "/home//foo/".
    In this case, you should ignore redundant slashes and return "/home/foo".

Summary: Very careful about corner cases, like "/", "/.", "..". 

 1 class Solution {
 2 public:
 3     void handleEntry(vector<string> &path_stack, string path_entry) {
 4         if(path_entry == "..") {
 5             if(path_stack.size() > 0)
 6                 path_stack.pop_back();
 7         }else if (path_entry != ".") 
 8                 path_stack.push_back(path_entry);
 9     }
10     
11     string simplifyPath(string path) {
12         string simple_path;
13         if(path.size() == 0)
14             return simple_path;
15         vector<string> path_stack;
16         string path_entry;
17         for(int i = 0; i < path.size(); i ++) {
18             if(path_entry.size() == 0 && path[i] == '/'){
19                 continue;
20             }else if (path_entry.size() != 0 && path[i] == '/') {
21                 handleEntry(path_stack, path_entry);
22                 path_entry.clear();
23             }else {
24                 path_entry.push_back(path[i]);
25             }
26         }
27         if(path_entry.size() > 0)
28             handleEntry(path_stack, path_entry);
29     
30         for(string item: path_stack) {
31             simple_path += "/";
32             simple_path += item;
33         }
34         if(simple_path.size() == 0)
35             return "/";
36         return simple_path;
37     }
38 };

 

posted @ 2013-10-29 12:50  假日笛声  阅读(218)  评论(0)  编辑  收藏  举报