leetcode 71. 简化路径

leetcode

class Solution {
public:
string simplifyPath(string path) {
        
        std::vector<std::string> arrPathParts;
        char lastChar = ' ';
        int begin = -1;
        int end = -1;
        int i = 0;
        while ( i < path.size() || begin >= 0 ) {
            
            if ( i < path.size() ) {
                
                if ( lastChar == '/' && path[i] != '/' ) {
                    
                    begin = i;
                    end = -1;
                    
                } else if ( lastChar != '/' && path[i] == '/' ) {
                    
                    end = i;
                }
                
                lastChar = path[i];
                ++i;
                
            } else {
                
                if ( end < 0 ) {
                    
                    end = path.size();
                }
            }
            
            if ( begin >= 0 && begin < end ) {
                
                std::string strPart = path.substr( begin, end - begin );
                if ( !strPart.empty() ) {
                    
                    if ( strPart == ".." ) {
                        
                        if ( !arrPathParts.empty() ) {
                            
                            arrPathParts.pop_back();
                        }
                        
                    } else if ( strPart != "." ) {
                        
                        arrPathParts.push_back( strPart );
                    }
                }
                
                begin = -1;
                end = -1;
            }
        }
        
        std::string strSimplifyPath;
        for ( int i = 0; i < arrPathParts.size(); ++i ) {
            
            strSimplifyPath += "/" + arrPathParts[i];
        }
        if ( strSimplifyPath.empty() ) {
            
            strSimplifyPath = "/";
        }
        
        return strSimplifyPath;
    }
};