Simplify Path

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".

 

把‘/’当做字符串之间的区分，然后分析字符串便可

.忽略

..回退

其它则全部按符号处理

 

class Solution {
public:
    string simplifyPath(string path) {
        string re = "";
        stack <string > sk;
        int i = 0;
        int len = path.length();
        while(i<len)
        {
            if(path[i] == '/')
            {
                i++;
                continue;
            }
            int j = 0;
            
            while(i+j < len && path[i+j]!= '/')j++;
            
            string temp = path.substr(i,j);
            
            if(temp == "..")
            {
                if(!sk.empty())
                sk.pop();
                i = i+2;
            }
            else if(temp == "."){
                i++;
                continue;
                }
            else
            {
                i = i +j;
                sk.push(temp);
            }
            
        }
        if(sk.empty())return "/";
        while(!sk.empty())
        {
            string temp = sk.top();
            re = '/' + temp + re;
            sk.pop();
        }
        return re;
    }
};