/********************************************

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".

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class Solution {

public:

string simplifyPath(string path) {

int start,end;

int l = path.size();

stack<string> mystack;

string result;

start = 0;

while(start < l)

{

if(path[start] == '/')

{

end = start+1;

while(path[end]!='/'&&end<l) end++;

string s = path.substr(start+1,end-start-1);

printf("%s\n",s.c_str());

if(s == ".." && mystack.empty()){start = end;continue;}

if(s == ".." && !mystack.empty()) mystack.pop();

else if (s!="." && !s.empty())

mystack.push(s);

start = end;

}

else

start++;

}

if(mystack.empty()) return "/";

while(!mystack.empty())

{

result.insert(0,mystack.top());

result.insert(0,"/");

mystack.pop();

}

return result;

}

};