堆栈实现java

无法通过此代码实现堆栈

UseStack.java

     class UseStack{
            public static void main(String[] args) {
                Scanner obj = new Scanner(System.in);
                System.out.println("Enter the size of Stack....");
                int n = obj.nextInt();
                Push push = new Push(n);
                Pop pop = new Pop(n);
                while(true){
                    System.out.println("1: Push");
                    System.out.println("2: pop");
                    System.out.println("3: Show");
                    int choice = obj.nextInt();;
                    switch(choice){
                        case 1:
                        push.push();
                        break;
                        case 2:
                        pop.pop();
                        break;
                        case 3:
                        push.show();    
                        break;
                        default:
                        System.out.println("Invalid Option");
                        break;
                    }
                }
            }
        }

class Stack {
    public int arr[];
    public  int top;
    public  int capacity;

    Stack(int size){
        this.arr = new int[size];
        this.capacity = size;
        this.top = -1;
    }
}

class Push extends Stack {
    Push(int size) {
        super(size);
    }

    private static Scanner obj;
    public void push(){
        obj = new Scanner(System.in);
        System.out.println("Enter Value to push...");
        int value = obj.nextInt();
        System.out.println("Value : "+value);
        if(top==capacity-1){
            System.out.println("StackOverflow");
            return;
        }
        else{
            top++;
            System.out.println("Top : "+top);
            arr[top]=value;
            System.out.println("Pushed... "+arr[top]);
        }
    }

    public void show(){
        if(top==-1){
            System.out.println("StackUnderFlow");
            return;
        }
        else{
            System.out.println("Stack Elements : ");
            for(int i=top;i>=0;i--){
                System.out.println(arr[i]+" ");
            }
        }       
    }
}

public class Pop extends Stack {

    Pop(int size) {
        super(size);
    }
    
    public void pop(){
        if(top==-1){
            System.out.println("StackUnderflow-pop");
            return;
        }
        else{
            System.out.println("Top : "+top);
            System.out.println("Poped.. "+arr[top]);
            top--;
        }
    }
    
}

Stack.java

     class UseStack{
            public static void main(String[] args) {
                Scanner obj = new Scanner(System.in);
                System.out.println("Enter the size of Stack....");
                int n = obj.nextInt();
                Push push = new Push(n);
                Pop pop = new Pop(n);
                while(true){
                    System.out.println("1: Push");
                    System.out.println("2: pop");
                    System.out.println("3: Show");
                    int choice = obj.nextInt();;
                    switch(choice){
                        case 1:
                        push.push();
                        break;
                        case 2:
                        pop.pop();
                        break;
                        case 3:
                        push.show();    
                        break;
                        default:
                        System.out.println("Invalid Option");
                        break;
                    }
                }
            }
        }

class Stack {
    public int arr[];
    public  int top;
    public  int capacity;

    Stack(int size){
        this.arr = new int[size];
        this.capacity = size;
        this.top = -1;
    }
}

class Push extends Stack {
    Push(int size) {
        super(size);
    }

    private static Scanner obj;
    public void push(){
        obj = new Scanner(System.in);
        System.out.println("Enter Value to push...");
        int value = obj.nextInt();
        System.out.println("Value : "+value);
        if(top==capacity-1){
            System.out.println("StackOverflow");
            return;
        }
        else{
            top++;
            System.out.println("Top : "+top);
            arr[top]=value;
            System.out.println("Pushed... "+arr[top]);
        }
    }

    public void show(){
        if(top==-1){
            System.out.println("StackUnderFlow");
            return;
        }
        else{
            System.out.println("Stack Elements : ");
            for(int i=top;i>=0;i--){
                System.out.println(arr[i]+" ");
            }
        }       
    }
}

public class Pop extends Stack {

    Pop(int size) {
        super(size);
    }
    
    public void pop(){
        if(top==-1){
            System.out.println("StackUnderflow-pop");
            return;
        }
        else{
            System.out.println("Top : "+top);
            System.out.println("Poped.. "+arr[top]);
            top--;
        }
    }
    
}

Push.java

     class UseStack{
            public static void main(String[] args) {
                Scanner obj = new Scanner(System.in);
                System.out.println("Enter the size of Stack....");
                int n = obj.nextInt();
                Push push = new Push(n);
                Pop pop = new Pop(n);
                while(true){
                    System.out.println("1: Push");
                    System.out.println("2: pop");
                    System.out.println("3: Show");
                    int choice = obj.nextInt();;
                    switch(choice){
                        case 1:
                        push.push();
                        break;
                        case 2:
                        pop.pop();
                        break;
                        case 3:
                        push.show();    
                        break;
                        default:
                        System.out.println("Invalid Option");
                        break;
                    }
                }
            }
        }

class Stack {
    public int arr[];
    public  int top;
    public  int capacity;

    Stack(int size){
        this.arr = new int[size];
        this.capacity = size;
        this.top = -1;
    }
}

class Push extends Stack {
    Push(int size) {
        super(size);
    }

    private static Scanner obj;
    public void push(){
        obj = new Scanner(System.in);
        System.out.println("Enter Value to push...");
        int value = obj.nextInt();
        System.out.println("Value : "+value);
        if(top==capacity-1){
            System.out.println("StackOverflow");
            return;
        }
        else{
            top++;
            System.out.println("Top : "+top);
            arr[top]=value;
            System.out.println("Pushed... "+arr[top]);
        }
    }

    public void show(){
        if(top==-1){
            System.out.println("StackUnderFlow");
            return;
        }
        else{
            System.out.println("Stack Elements : ");
            for(int i=top;i>=0;i--){
                System.out.println(arr[i]+" ");
            }
        }       
    }
}

public class Pop extends Stack {

    Pop(int size) {
        super(size);
    }
    
    public void pop(){
        if(top==-1){
            System.out.println("StackUnderflow-pop");
            return;
        }
        else{
            System.out.println("Top : "+top);
            System.out.println("Poped.. "+arr[top]);
            top--;
        }
    }
    
}

Pop.java

     class UseStack{
            public static void main(String[] args) {
                Scanner obj = new Scanner(System.in);
                System.out.println("Enter the size of Stack....");
                int n = obj.nextInt();
                Push push = new Push(n);
                Pop pop = new Pop(n);
                while(true){
                    System.out.println("1: Push");
                    System.out.println("2: pop");
                    System.out.println("3: Show");
                    int choice = obj.nextInt();;
                    switch(choice){
                        case 1:
                        push.push();
                        break;
                        case 2:
                        pop.pop();
                        break;
                        case 3:
                        push.show();    
                        break;
                        default:
                        System.out.println("Invalid Option");
                        break;
                    }
                }
            }
        }

class Stack {
    public int arr[];
    public  int top;
    public  int capacity;

    Stack(int size){
        this.arr = new int[size];
        this.capacity = size;
        this.top = -1;
    }
}

class Push extends Stack {
    Push(int size) {
        super(size);
    }

    private static Scanner obj;
    public void push(){
        obj = new Scanner(System.in);
        System.out.println("Enter Value to push...");
        int value = obj.nextInt();
        System.out.println("Value : "+value);
        if(top==capacity-1){
            System.out.println("StackOverflow");
            return;
        }
        else{
            top++;
            System.out.println("Top : "+top);
            arr[top]=value;
            System.out.println("Pushed... "+arr[top]);
        }
    }

    public void show(){
        if(top==-1){
            System.out.println("StackUnderFlow");
            return;
        }
        else{
            System.out.println("Stack Elements : ");
            for(int i=top;i>=0;i--){
                System.out.println(arr[i]+" ");
            }
        }       
    }
}

public class Pop extends Stack {

    Pop(int size) {
        super(size);
    }
    
    public void pop(){
        if(top==-1){
            System.out.println("StackUnderflow-pop");
            return;
        }
        else{
            System.out.println("Top : "+top);
            System.out.println("Poped.. "+arr[top]);
            top--;
        }
    }
    
}

问题

在此实现中，pop（）不起作用

我认为对于这个Pop类，需要同时扩展Stack和Push类，因为这在java中是不可能的，如果我错了，有人能帮我解决这个问题吗…

Pop（）

不起作用，因为推送和Pop使用不同的对象

您不需要为push和pop定义另一个类，它们是在堆栈类中添加这些函数的操作

class Stack {
   ... // members and constructor
   public void push(){..}
   public void pop(){..}
   public void show(){..}
}

并创建一个Stack类的对象，用于push、pop和show

Stack s = new Stack(n);
while(true){
    ... 
    switch(choice){
        case 1:
        s.push();
        break;
        case 2:
        s.pop();
        break;
        case 3:
        s.show();    
        break;
        default:
        System.out.println("Invalid Option");
        break;
    }
}

---

为什么push和pop操作会扩展

堆栈

类？你不会写

狗延伸动物

和

吠叫延伸狗

，是吗？@Kayaman先生你能再纠正我一下吗？你不需要叫我先生。我只是问你为什么有

Push

和

Pop

类？为什么

Stack

类中不存在

push（）

和

pop（）

方法？您需要在问题中包含任何错误。但是代码在设计上是错误的，所以您应该首先修复您的设计（删除

Push

和

Pop

类），然后尝试让代码正常工作。问题是Push和popping在同一数据结构上不起作用。当用户发出“push”命令时，您在

push

堆栈上调用

push（）

，从而将数据添加到

push

堆栈中；与此同时，“pop”堆栈仍然是空的。现在，当用户发出“pop”命令时，您调用

pop

堆栈的

pop（）

方法，空的

pop

堆栈中没有任何东西可以弹出。@ItazakhStern知道什么？因为你完全错误的设计，你实际上使用了多个对象，但是你认为你可以把它们当作一个堆栈来对待？我建议你开始读这本书，因为你知道的并不像你想象的那么多。@ItazakhStern：“我知道这个”？如果你知道的话，为什么要问这个问题呢？我的意思是像push和pop这样的操作可以在stack类中定义