循环队列/队列

/*
循环队列
enqueue: tail_loc = (tail_loc+1)%queue_size
dequeue: head = (head+1)%queue_size
empty:head=tail
full:(head+1)%queue_size = head
curr queue size: (tail - head))%queeu_size
*/

template<typename T>
class Queue{
private:
	int queue_size;
	T *data;
	int head_loc;
	int tail_loc;

public:
	Queue(int queue_size=100);
	~Queue();
	void push(const T value);
	void pop();
	T front();
	int get_size();
	bool full();
	bool empty();
};


template<typename T>
Queue<T>::Queue(int size){
	head_loc = 0;
	tail_loc = 0;
	queue_size = size;
	data = new T[size];
}

template<typename T>
Queue<T>::~Queue(){
	delete []data;
	data = nullptr;
	head_loc = 0;
	tail_loc = 0;
	queue_size = 0;
}

template<typename T>
void Queue<T>::push(const T value){
	if(full())
		std::cerr<<"queue full"<<endl;
	data[tail_loc] = value;
	tail_loc = (tail_loc+1) % queue_size; 
}

template<typename T>
T Queue<T>::front(){
	if(empty())
		std::cerr<<"queue empty"<<endl;
	return data[head_loc];
}


template<typename T>
void Queue<T>::pop(){
	if(empty())
		std::cerr<<"queue empty"<<endl;
	head_loc = (head_loc+1) % queue_size;
}


template<typename T>
bool Queue<T>::empty(){
	return head_loc==tail_loc;
}

template<typename T>
bool Queue<T>::full(){
	return (tail_loc+1)%queue_size==head_loc;
}

template<typename T>
int Queue<T>::get_size(){
	return (tail_loc - head_loc + queue_size)%queue_size;
}


void print_queue(Queue<int> q){
	while(!q.empty()){
		cout<<q.front()<<endl;
		q.pop();
	}
}

int main(int argc, char const *argv[]){
	Queue<int> q(100);
	q.push(1);
	q.push(2);
	q.push(3);
	q.push(4);

	cout<<q.front()<<endl;

	q.pop();
	q.pop();
	
	cout<<q.front()<<endl;

	q.push(7);
	print_queue(q);

	return 0;
}