my favorite implementation

queues/circular_queue_III.py

@@ -0,0 +1,70 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+# author: bt3gl
+# this is my favorite implementation <3
+
+
+class Node:
+    def __init__(self, value, next=None):
+        self.value = value
+        self.next = next
+
+
+class CircularQueue:
+
+    def __init__(self, k: int):
+      
+        self.capacity = k
+        self.count = 0
+        self.head = None
+        self.tail = None
+        
+    def enqueue(self, value: int) -> bool:
+
+        if self.count == self.capacity:
+            return False
+        
+        if self.count == 0:
+            self.head = Node(value)
+            self.tail = self.head
+        else:
+            new_node = Node(value)
+            self.tail.next = new_node
+            self.tail = new_node
+          
+        self.count += 1
+      
+        return True
+
+    def dequeue(self) -> bool:
+
+        if self.count == 0:
+            return False
+          
+        self.head = self.head.next
+        self.count -= 1
+      
+        return True
+
+    def front(self) -> int:
+
+        if self.count == 0:
+            return -1
+          
+        return self.head.value
+
+    def rear(self) -> int:
+
+        if self.count == 0:
+            return -1
+          
+        return self.tail.value
+    
+    def is_empty(self) -> bool:
+
+        return self.count == 0
+
+    def is_full(self) -> bool:
+
+        return self.count == self.capacity
+