void PushDir(MyStackArray <string> stack, StringBuilder sb)
{
var dir = sb.ToString();
sb.Clear();
switch (dir)
{
case "":
return;
case ".":
return;
case "..":
if (!stack.IsEmpty())
{
stack.Pop();
}
return;
default:
stack.Push(dir);
return;
}
}
/* A shorter solution by using String.Split
* potentially with worse performance
* Runtime: 192 ms, faster than 5.02% of C# online submissions for Simplify Path.
* Memory Usage: 25 MB, less than 72.15% of C# online submissions for Simplify Path.
* using System.Linq;
* public string SimplifyPath(string path)
* {
* if (path.Length == 1) return "/";
* var stack = new MyStackArray<string>();
* var files = path.Split('/').Where(file => file.Length != 0 && file != ".");
* foreach (var file in files)
* {
* if (file == "..")
* {
* if (!stack.IsEmpty())
* stack.Pop();
* }
* else
* {
* stack.Push(file);
* }
* }
* return "/" + String.Join("/", stack.AsReversedArray());
* } */
public string SimplifyPath(string path)
{
if (path.Length == 1)
{
return("/");
}
var stack = new MyStackArray <string>();
var sb = new StringBuilder();
var i = 0;
while (i != path.Length)
{
switch (path[i])
{
case '.':
i += 1;
sb.Append('.');
continue;
case '/':
i += 1;
while (i != path.Length && path[i] == '/')
{
i += 1;
}
PushDir(stack, sb);
continue;
default:
sb.Append(path[i]);
i += 1;
continue;
}
}
if (sb.Length != 0)
{
PushDir(stack, sb);
}
return("/" + String.Join("/", stack.AsReversedArray()));
}