1+ // 实现循环队列 阿里面试题
2+ 3+ // Runtime: 32 ms, faster than 84.47% of C++ online submissions for Design Circular Queue.
4+ // Memory Usage: 16.5 MB, less than 72.73% of C++ online submissions for Design Circular Queue.
5+ 6+ class MyCircularQueue
7+ {
8+ public:
9+ /* * Initialize your data structure here. Set the size of the queue to be k. */
10+ MyCircularQueue (int k) : data(k + 1 , 0 )
11+ {
12+ front = 0 ;
13+ rear = 0 ;
14+ }
15+ 16+ /* * Insert an element into the circular queue. Return true if the operation is successful. */
17+ bool enQueue (int value)
18+ {
19+ if (!isFull ())
20+ {
21+ rear = (rear + 1 ) % data.size ();
22+ data[rear] = value;
23+ 24+ return true ;
25+ }
26+ else
27+ {
28+ return false ;
29+ }
30+ }
31+ 32+ /* * Delete an element from the circular queue. Return true if the operation is successful. */
33+ bool deQueue ()
34+ {
35+ if (!isEmpty ())
36+ {
37+ front = (front + 1 ) % data.size ();
38+ return true ;
39+ }
40+ else
41+ {
42+ return false ;
43+ }
44+ }
45+ 46+ /* * Get the front item from the queue. */
47+ int Front ()
48+ {
49+ if (!isEmpty ())
50+ {
51+ return data[(front + 1 ) % data.size ()];
52+ }
53+ else
54+ {
55+ return -1 ;
56+ }
57+ }
58+ 59+ /* * Get the last item from the queue. */
60+ int Rear ()
61+ {
62+ if (!isEmpty ())
63+ {
64+ return data[rear];
65+ }
66+ else
67+ {
68+ return -1 ;
69+ }
70+ }
71+ 72+ /* * Checks whether the circular queue is empty or not. */
73+ bool isEmpty ()
74+ {
75+ return rear == front;
76+ }
77+ 78+ /* * Checks whether the circular queue is full or not. */
79+ bool isFull ()
80+ {
81+ return (rear + 1 ) % data.size () == front;
82+ }
83+ private:
84+ int front; // 头部索引
85+ int rear; // 尾部索引
86+ 87+ vector<int > data; // 数据存储
88+ };
89+ 90+ /* *
91+ * Your MyCircularQueue object will be instantiated and called as such:
92+ * MyCircularQueue* obj = new MyCircularQueue(k);
93+ * bool param_1 = obj->enQueue(value);
94+ * bool param_2 = obj->deQueue();
95+ * int param_3 = obj->Front();
96+ * int param_4 = obj->Rear();
97+ * bool param_5 = obj->isEmpty();
98+ * bool param_6 = obj->isFull();
99+ */
0 commit comments