upd

algorithms/labs/lab8/code/hash/1.py

@@ -0,0 +1,60 @@
+class Node:
+    def __init__(self, key, val):
+        self.key = key
+        self.val = val
+        self.prev = None
+        self.next = None
+
+
+class LRUCache:
+    def __init__(self, capacity: int):
+        self.cap = capacity
+        self.cache = {}
+        self.left = Node(0, 0)
+        self.right = Node(0, 0)
+        self.left.next = self.right
+        self.right.prev = self.left
+
+    def remove(self, node):
+        p, n = node.prev, node.next
+        p.next = n
+        n.prev = p
+
+    def insert(self, node):
+        p, n = self.right.prev, self.right
+        p.next = node
+        node.prev = p
+        node.next = n
+        n.prev = node
+
+    def get(self, key: int) -> int:
+        if key not in self.cache:
+            return -1
+        node = self.cache[key]
+        self.remove(node)
+        self.insert(node)
+        return node.val
+
+    def put(self, key: int, value: int) -> None:
+        if key in self.cache:
+            self.remove(self.cache[key])
+        node = Node(key, value)
+        self.cache[key] = node
+        self.insert(node)
+        if len(self.cache) > self.cap:
+            lru = self.left.next
+            self.remove(lru)
+            del self.cache[lru.key]
+
+
+if __name__ == "__main__":
+    lru = LRUCache(2)
+    lru.put(1, 1)
+    lru.put(2, 2)
+    print(lru.get(1))
+    lru.put(3, 3)
+    print(lru.get(2))
+    lru.put(4, 4)
+    print(lru.get(1))
+    print(lru.get(3))
+    print(lru.get(4))