leetcode——71——Simplify Path

"/home/"

"/home"

"/a/./b/../../c/"

"/c"

class Solution
{
public:
string simplifyPath(string path)
{
stack<string> ss; // 记录路径名
for(int i = 0; i < path.size(); )
{
// 跳过斜线'/'
while(i < path.size() && '/' == path[i])
++ i;
// 记录路径名
string s = "";
while(i < path.size() && path[i] != '/')
s += path[i ++];
// 如果是".."则需要弹栈，否则入栈
if(".." == s && !ss.empty())
ss.pop();
else if(s != "" && s != "." && s != "..")
ss.push(s);
}
// 如果栈为空，说明为根目录，只有斜线'/'
if(ss.empty())
return "/";
// 逐个连接栈里的路径名
string s = "";
while(!ss.empty())
{
s = "/" + ss.top() + s;
ss.pop();
}
return s;
}
};