class Solution {
public:
string simplifyPath(string path) {
stringstream ss(path);
string str;
string res;
vector vec;
while (getline(ss, str, '/'))
{
if (str == "" || str == ".")
{
continue;
}
if (str == ".." && !vec.empty())
{
vec.pop_back();
}
else if (str != "..")
{
vec.push_back(str);
}
}
for (auto s : vec)
{
res.append("/");
res.append(s);
}
return res.empty() ? "/" : res;
}
};