public void Add(int key, int value)
{
// just need to update value and move it to the top
if (map.ContainsKey(key))
{
LRUNode node = map[key];
doubleLinkedList.RemoveNode(node);
node.Value = value;
doubleLinkedList.AddToTop(node);
}
else
{
// if cache is full, then remove the least recently used node
if (count == capacity)
{
LRUNode lru = doubleLinkedList.RemoveLRUNode();
map.Remove(lru.Key);
count--;
}
// add a new node
LRUNode node = new LRUNode(key, value);
doubleLinkedList.AddToTop(node);
map[key] = node;
count++;
}
}
/// <summary>
/// code review:
/// I like to learn from discussion post:
/// https://leetcode.com/problems/lru-cache/discuss/753750/C-Implementation-using-Dictionary-and-Double-Linked-List
/// </summary>
/// <param name="key"></param>
/// <param name="value"></param>
public void Put(int key, int value)
{
var update = map.ContainsKey(key);
var reachMaximum = map.Count == capacity;
if (update)
{
list.RemoveNode(map[key]);
map[key].Value = value; // update
list.AddToFront(map[key]);
}
else
{
if (reachMaximum)
{
var removed = list.RemoveLRUNode();
map.Remove(removed.Key);
// insert a new node
var node = new Node(key, value);
list.AddToFront(node);
map.Add(key, node);
}
else
{
// insert a new node
var node = new Node(key, value);
list.AddToFront(node);
map.Add(key, node);
}
}
}
/// <summary>
/// code review:
/// I like to learn from discussion post:
/// https://leetcode.com/problems/lru-cache/discuss/753750/C-Implementation-using-Dictionary-and-Double-Linked-List
/// </summary>
/// <param name="key"></param>
/// <param name="value"></param>
public void Put(int key, int value)
{
var update = map.ContainsKey(key);
var reachMaximum = map.Count == capacity;
if (reachMaximum)
{
if (update)
{
list.RemoveNode(map[key]);
map[key].Value = value; // update
list.AddToTail(map[key]);
}
else
{
var removed = list.RemoveLRUNode();
map.Remove(removed.Key);
// insert a new node
var node = new Node(key, value);
list.AddToTail(node);
map.Add(key, node);
}
return;
}
// two cases
if (update)
{
var removed = list.RemoveLRUNode();
//removed.Value = value; // caught by Leetcode online judge
map[key].Value = value;
list.AddToTail(removed);
}
else
{
// insert a new node
var node = new Node(key, value);
list.AddToTail(node);
map.Add(key, node);
}
}
public void Put(int key, int value) {
if (map.ContainsKey(key))
{
LRUNode node = map[key];
doubleLinkedList.RemoveNode(node);
node.Value = value;
doubleLinkedList.AddToTop(node);
}
else
{
if (count==capacity) {
LRUNode lru = doubleLinkedList.RemoveLRUNode();
map.Remove(lru.Key);
count--;
}
LRUNode node = new LRUNode(key, value);
doubleLinkedList.AddToTop(node);
map[key] = node;
count++;
}
}