Simplify Path

 1 class Solution {
 2 public:
 3     string simplifyPath( string path ) {
 4         list<string> dirList;
 5         size_t prev = 0, i = 0;
 6         while( ++i < path.size() ) {
 7             if( path[i] == ‘/‘ ) { 
 8                 if( i-prev-1 > 0 ) {
 9                     string curDir = path.substr( prev+1, i-prev-1 );
10                     if( curDir == ".." ) {
11                         if( !dirList.empty() ) { dirList.pop_back(); }
12                     } else if( curDir != "." ) {
13                         dirList.push_back( curDir );
14                     }
15                 }
16                 prev = i;
17             }
18         }
19         if( i-prev-1 > 0 ) {
20             string curDir = path.substr( prev+1, i-prev-1 );
21             if( curDir == ".." ) {
22                 if( !dirList.empty() ) { dirList.pop_back(); }
23             } else if( curDir != "." ) {
24                 dirList.push_back( curDir );
25             }
26         }
27         string result = "";
28         for( auto iter = dirList.begin(); iter != dirList.end(); ++iter ) {
29             result += "/" + *iter;
30         }
31         if( result.empty() ) { result = "/"; }
32         return result;
33     }
34 };