设计循环队列 (Design Circular Queue)
该代码实现了一个循环队列的数据结构,支持基本的队列操作,如入队、出队、获取队列头部和尾部元素、检查队列是否为空或已满。
题目描述
设计一个固定大小的循环队列。实现 MyCircularQueue 类:
MyCircularQueue(k):构造函数,初始化队列大小为k,队列为空。enQueue(value):向队列尾部添加元素value。返回true如果成功,false如果队列已满。deQueue():从队列头部删除元素。返回true如果成功,false如果队列为空。front():获取队列头部元素。如果队列为空,返回-1。rear():获取队列尾部元素。如果队列为空,返回-1。isEmpty():检查队列是否为空。isFull():检查队列是否已满。free():释放队列的内存。
题目地址
代码实现
typedef struct {
int size;
int front;
int back;
int *element;
} MyCircularQueue;
MyCircularQueue* myCircularQueueCreate(int k) {
MyCircularQueue* obj = (MyCircularQueue*)malloc(sizeof(MyCircularQueue));
obj->size = k + 1;
obj->front = obj->back = 0;
obj->element = (int*)malloc(sizeof(int)*obj->size);
return obj;
}
bool myCircularQueueEnQueue(MyCircularQueue* obj, int value) {
if(obj->front == (obj->back + 1)%obj->size)return false;
obj->element[obj->back] = value;
obj->back = (obj->back + 1)%obj->size;
return true;
}
bool myCircularQueueDeQueue(MyCircularQueue* obj) {
if(obj->front == obj->back)return false;
obj->front = (obj->front + 1)%obj->size;
return true;
}
int myCircularQueueFront(MyCircularQueue* obj) {
if(obj->front == obj->back)return -1;
return obj->element[obj->front];
}
int myCircularQueueRear(MyCircularQueue* obj) {
if(obj->front == obj->back)return -1;
return obj->element[(obj->back - 1 + obj->size)%obj->size];
}
bool myCircularQueueIsEmpty(MyCircularQueue* obj) {
return obj->front == obj->back;
}
bool myCircularQueueIsFull(MyCircularQueue* obj) {
return obj->front == (obj->back + 1)%obj->size;
}
void myCircularQueueFree(MyCircularQueue* obj) {
free(obj->element);
free(obj);
}
/**
* Your MyCircularQueue struct will be instantiated and called as such:
* MyCircularQueue* obj = myCircularQueueCreate(k);
* bool param_1 = myCircularQueueEnQueue(obj, value);
* bool param_2 = myCircularQueueDeQueue(obj);
* int param_3 = myCircularQueueFront(obj);
* int param_4 = myCircularQueueRear(obj);
* bool param_5 = myCircularQueueIsEmpty(obj);
* bool param_6 = myCircularQueueIsFull(obj);
* myCircularQueueFree(obj);
*/