Leetcode Simplify Path

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

For example,
path = "/home/", => "/home"

path = "/a/./b/../../c/", => "/c"




对unix-style的path进行了下了解，.可以忽略不计,..返回上一级目录，因此我们就需要一个结构来存储上一级目录，也就是后进先进，当然理所当然的就是栈结构。然后需要注意的是，栈在为空的时候不能调用pop操作，以及最后输出结果时，路径的顺序不要弄反了 - -




代码如下:

class Solution {
public:
    string simplifyPath(string path) {
        stack<string> stack;
        stringstream ss(path);
        string tmp;
        while(getline(ss,tmp,'/'))
        {
            if(tmp == "." || tmp == "") continue;
            else if(tmp == ".." && !stack.empty()) 
                stack.pop();
            else if(tmp != "..")
                stack.push(tmp);
        }
        
        string result;
        while(!stack.empty())
        {
            result = "/"+stack.top() + result;
            stack.pop();
        }
        
        return result.empty()?"/":result;
    }
};