棧和隊列--第3集

轉載請註明出處：http://blog.csdn.net/u011569040/article/details/46004687

棧的構造和應用：

public class MyStack {
	
	private long[] arr;
	private int top;
	
	//默認的構造方法
	public MyStack(){
		arr = new long[10];
		top = -1;
	}
	
	//帶參數構造方法，參數爲數組初始化大小
	public MyStack(int maxsize){
		arr = new long[maxsize];
		top = -1;
	}
	
	//添加數據
	public void push(int value){
		arr[++top] = value;
	}
	
	//移除數據
	public long pop(){
		return arr[top--];
	}
	
	//查看數據
	public long peek(){
		return arr[top];
	}
	
	//判斷是否爲空
	public boolean isEmply(){
		return top == -1;
	}
	
	//判斷是否滿了
	public boolean isFull(){
		return top ==arr.length  -1;
	}
	
	public void print(){
		for(long num : arr){
			System.out.print(num + ",");
		}
	}
}

public class Test {

	public static void main(String[] args) {
		MyStack ms = new MyStack(4);
		ms.push(23);
		ms.push(12);
		ms.push(1);
		ms.push(9);
		
		ms.print();
		System.out.println(ms.isEmply());
		System.out.println(ms.isFull());
		
		System.out.println(ms.peek());
		
		while(!ms.isEmply()){
			System.out.print(ms.pop() + ",");
		}
		
		System.out.println(ms.isEmply());
		System.out.println(ms.isFull());
		
		ms.print();
	}
}

結果：

列隊：

public class MyQueue {
	//底層使用數組
	private long[] arr;
	//有效數據的大小
	private int elements;
	//對頭
	private int front;
	//隊尾
	private int end;
	
	//默認構造方法
	public MyQueue(){
		arr = new long[10];
		elements = 0;
		front = 0;
		end = -1;
	}
	
	//帶參數的構造方法，參數爲數組的大小
	public MyQueue(int maxsize){
		arr = new long[maxsize];
		elements = 0;
		front = 0;
		end = -1;
	}
	
	//添加數據,從隊尾加入
	public void insert(long value){
		arr[++end] = value;
		elements++;
		
	}
	
	//刪除數據，從對頭刪除
	public long remove(){
		elements--;
		return arr[front++];
	}
	
	//查看數據，從對頭查看
	public long peek(){
		return arr[front];
	}
	
	//判斷是否爲空
	public boolean isEmpty(){
		return elements == 0;
	}
	
	//判斷是否滿了
	public boolean isFull(){
		return elements == arr.length ;
	}
}

public class TestMyQueue {

	public static void main(String[] args) {
		MyQueue mq = new MyQueue(4);
		mq.insert(23);
		mq.insert(45);
		mq.insert(13);
		mq.insert(1);
		
		System.out.println(mq.isFull());
		System.out.println(mq.isEmpty());
		
		System.out.println(mq.peek());
		System.out.println(mq.peek());
		
		while(!mq.isEmpty()){
			System.out.println(mq.remove() + " ");
		}
	}
}

但是現在如果再insert（）數據就會報錯

所以要用循環隊列：

只需要修改insert（）和remove（）：

//添加數據,從隊尾加入
	public void insert(long value){
		if(end == arr.length - 1){
			end = -1;
		}
		arr[++end] = value;
		elements++;
		
	}
	
	//刪除數據，從對頭刪除
	public long remove(){
		long value = arr[front++];
		if(front == arr.length){
			front = 0;
		}
		elements--;
		return value ;
	}

public class TestMyQueue {

	public static void main(String[] args) {
		MyCycleQueue mq = new MyCycleQueue(4);
		mq.insert(23);
		mq.insert(45);
		mq.insert(13);
		mq.insert(1);
		
		System.out.println(mq.isFull());
		System.out.println(mq.isEmpty());
		
//		System.out.println(mq.peek());
//		System.out.println(mq.peek());
		
		while(!mq.isEmpty()){
			System.out.println(mq.remove() + " ");
		}
		
		mq.insert(23);
		mq.insert(45);
		mq.insert(13);
		mq.insert(1);
		
		while(!mq.isEmpty()){
			System.out.println("xie "+mq.remove() + " ");
		}
	}
}

結果：