static object Solve()
{
var s = Console.ReadLine();
var q = new DQ <char>();
var rev = false;
foreach (var c in s)
{
if (c == 'R')
{
rev = !rev;
}
else
{
if (rev)
{
if (q.Length > 0 && q.First == c)
{
q.PopFirst();
}
else
{
q.PushFirst(c);
}
}
else
{
if (q.Length > 0 && q.Last == c)
{
q.PopLast();
}
else
{
q.PushLast(c);
}
}
}
}
if (rev)
{
return(string.Join("", Enumerable.Range(0, q.Length).Select(i => q[i]).Reverse()));
}
else
{
return(string.Join("", Enumerable.Range(0, q.Length).Select(i => q[i])));
}
}
static void Main()
{
var n = int.Parse(Console.ReadLine());
var qs = new int[n].Select(_ => Console.ReadLine().Split());
var dq = new DQ <int>(Math.Min(1000000, n));
var actions = new Dictionary <string, Action <string[]> >();
actions["insert"] = q => dq.PushFirst(int.Parse(q[1]));
actions["delete"] = q => dq.RemoveFirst(int.Parse(q[1]));
actions["deleteFirst"] = q => dq.PopFirst();
actions["deleteLast"] = q => dq.PopLast();
foreach (var q in qs)
{
actions[q[0]](q);
}
Console.WriteLine(string.Join(" ", Enumerable.Range(0, dq.Length).Select(i => dq[i])));
}
static void Main()
{
int n = int.Parse(Console.ReadLine());
var r = new List <int>();
var dq = new DQ <int>();
for (int k = n; k > 0; k--)
{
var q = Array.ConvertAll(Console.ReadLine().Split(), int.Parse);
if (q[0] == 0)
{
if (q[1] == 0)
{
dq.PushFirst(q[2]);
}
else
{
dq.PushLast(q[2]);
}
}
else if (q[0] == 1)
{
r.Add(dq[q[1]]);
}
else
{
if (q[1] == 0)
{
dq.PopFirst();
}
else
{
dq.PopLast();
}
}
}
Console.WriteLine(string.Join("\n", r));
}
static void Main()
{
var n = int.Parse(Console.ReadLine());
var s = Console.ReadLine();
var q = new DQ <int>();
var stack = new Stack <int>();
int RemoveAndGetFirst(int k)
{
for (int i = 0; i < k; i++)
{
stack.Push(q.PopFirst());
}
var r = q.PopFirst();
for (int i = 0; i < k; i++)
{
q.PushFirst(stack.Pop());
}
return(r);
}
int RemoveAndGetLast(int k)
{
for (int i = 0; i < k; i++)
{
stack.Push(q.PopLast());
}
var r = q.PopLast();
for (int i = 0; i < k; i++)
{
q.PushLast(stack.Pop());
}
return(r);
}
Console.SetOut(new System.IO.StreamWriter(Console.OpenStandardOutput())
{
AutoFlush = false
});
for (int i = 0; i < n; i++)
{
var c = s[i];
if (c == 'L')
{
q.PushFirst(i + 1);
}
else if (c == 'R')
{
q.PushLast(i + 1);
}
else if (c < 'D')
{
var k = c - 'A';
if (k < q.Length)
{
Console.WriteLine(RemoveAndGetFirst(k));
}
else
{
Console.WriteLine("ERROR");
}
}
else
{
var k = c - 'D';
if (k < q.Length)
{
Console.WriteLine(RemoveAndGetLast(k));
}
else
{
Console.WriteLine("ERROR");
}
}
}
Console.Out.Flush();
}