private static void Test()
{
Bst bst = new Bst();
bst.Insert(2);
bst.Insert(5);
bst.Insert(3);
Console.WriteLine(bst.Exists(2) ? "true" : "false");
Console.WriteLine(bst.Exists(4) ? "true" : "false");
Console.WriteLine(bst.Next(4)?.Value.ToString() ?? "none");
Console.WriteLine(bst.Prev(4)?.Value.ToString() ?? "none");
bst.Delete(5);
Console.WriteLine(bst.Next(4)?.Value.ToString() ?? "none");
Console.WriteLine(bst.Prev(4)?.Value.ToString() ?? "none");
}
public static void Solve()
{
using (var input = new StreamReader("bstsimple.in"))
{
using (var output = new StreamWriter("bstsimple.out"))
{
Bst bst = new Bst();
while (true)
{
string[] line = input.ReadLine()?.Trim().Split();
if (line == null)
{
break;
}
switch (line[0])
{
case "insert":
bst.Insert(long.Parse(line[1]));
break;
case "delete":
bst.Delete(long.Parse(line[1]));
break;
case "exists":
output.WriteLine(bst.Exists(long.Parse(line[1])) ? "true" : "false");
break;
case "next":
output.WriteLine(bst.Next(long.Parse(line[1]))?.Value.ToString() ?? "none");
break;
case "prev":
output.WriteLine(bst.Prev(long.Parse(line[1]))?.Value.ToString() ?? "none");
break;
}
}
}
}
}