private void PlaceTail(CustomLRUNode node)
{
node.Prev = _cacheTail.Prev;
node.Next = _cacheTail;
node.Prev.Next = node;
node.Next.Prev = node;
}
public CustomLRUCache(int capacity)
{
_cache = new Dictionary <int, CustomLRUNode>();
_cacheHead = new CustomLRUNode(-1, -1);
_cacheTail = new CustomLRUNode(-1, -1);
_cacheHead.Next = _cacheTail;
_cacheTail.Prev = _cacheHead;
_capacity = capacity;
}
public void Put(int key, int value)
{
if (_cache.ContainsKey(key))
{
MoveToTail(key);
_cache[key].Data = value;
}
else
{
var newNode = new CustomLRUNode(key, value);
PlaceTail(newNode);
_cache[key] = newNode;
}
if (_cache.Count > _capacity)
{
_cache.Remove(_cacheHead.Next.Key);
Remove(_cacheHead.Next);
}
}
private void Remove(CustomLRUNode node)
{
node.Prev.Next = node.Next;
node.Next.Prev = node.Prev;
}