public void Put(int key, int value)
{
int oldValue = Get(key);
if (oldValue == -1)
{
if (_linkedList.Count + 1 > _capacity)
{
var tail = _linkedList.Last;
int removeKey = tail.Value.Key;
_hash.Remove(removeKey);
_linkedList.RemoveLast();
}
// add as new head
CacheData data = new CacheData(key, value);
_linkedList.AddFirst(new LinkedListNode <CacheData>(data));
var head = _linkedList.First;
_hash.Add(key, head);
}
// key exist but value is not the same. update key
else
{
_hash[key].Value.Value = value;
}
}
public T Pop()
{
if (List.Count <= 0)
{
throw new Exception("Unable to pop item. Stack is empty.");
}
T topItem = List.Last.Value;
List.RemoveLast();
return(topItem);
}
/// <inheritdoc/>
/// <exception cref="InvalidOperationException">The key is already added.</exception>
public void AddToBottom(K key, V value)
{
var valueContainer = list.AddLast(new Pair <K, V>(key, value));
try {
map.Add(key, valueContainer);
}
catch (Exception e) {
list.RemoveLast();
if (e is ArgumentException)
{
throw new InvalidOperationException(Strings.ExCollectionAlreadyContainsItemWithSpecifiedKey);
}
else
{
throw;
}
}
}
public void Set(int key, int value)
{
if (Get(key) != -1)
{
LinkedListNode <int> node = _values[key];
node.Value = value;
}
else
{
if (_linkedList.Count + 1 > _capacity)
{
var lastKey = _values.FirstOrDefault(x => x.Value.Equals(_linkedList.Last)).Key;
if (lastKey > 0)
{
_values.Remove(lastKey);
}
_linkedList.RemoveLast();
}
LinkedListNode <int> node = _linkedList.AddFirst(value);
_values.Add(key, node);
}
}
public void RemoveLast() => linkedList.RemoveLast();