[JAVA]Stack / Queue 개념 스텍

classMemory

abstract class Memory {
    protected int [] m;
    protected int count;
    Memory(){//생성자
        m =new int [20];
        count =0;
    }
    public void push(int i) {
        if(full()) {
            m[count++]=i;
        }
    }    
    abstract int pop();
    abstract boolean full();
    abstract boolean empty();
}
 

class Stack extends Memory 메모리 한테서 상속

 
public class Stack extends Memory {
 
    @Override
    int pop() {
        if(empty()) {
            return m[--count];
        }
        else    
            return -1;
    }
 
    @Override
    boolean full() {
        if(count == 20) {
            System.out.println("Full");
 
            return false;
        }
        else {
            return true;
        }
    }
    @Override
    boolean empty() {
        if(count==0) {
            System.out.println("엠프리");
            count = 0;
            return false;
        }
        else 
            return true;
        
    }
 
 
}
 

 class Queue extends Memory 

 
public class Queue extends Memory{
    int front;
    Queue(){
        front =0;
    }
    @Override
    int pop() {
        if (empty()) {
            return m[front];
        }
        else {
            return -1;
        }
    }
    @Override
    boolean full() {
        if (count == 20 && front ==0) {
            System.out.println("가득");
            return false;
        }
        else {
            return true;
        }
        
    }
    @Override
    boolean empty() {
        if(count == front) {
            System.out.println("엠프리");
            count = front =0;
            return false;
                    
        }
        else 
            return true;
        
        
    }
}
 
 

class SQmgn (mian)

import java.util.Scanner;
 
public class SQmgn {
    public static void main(String[] args) {
        Memory m = null;          //초기화를 해주어야한다
        Stack ms = new Stack();
        Queue mq = new Queue();
        
        Scanner s = new Scanner(System.in);
        int c = 0;
        while(c!=3) {
            System.out.println("1.Stack  2.Queue");
            System.out.print("선택 : ");
            c = s.nextInt();
            switch(c) {
            case 1 : //stack
                m = ms;
                System.out.println("1.Push  2.Pop");
                System.out.print("선택 : ");
                int sc = s.nextInt();
                if(sc == 1) {
                    System.out.print("입력 : ");
                    m.push(s.nextInt());
                }
                
                if(sc == 2) {
                    System.out.println(m.pop());
                }
                break;
            case 2 : //queue
                m = mq;
                System.out.println("1.Push  2.Pop");
                System.out.print("선택 : ");
                int qc = s.nextInt();
                if(qc == 1) {
                    System.out.print("입력 : ");
                    m.push(s.nextInt());
                }
                
                if(qc == 2) {
                    System.out.println(m.pop());
                }
                break;
            }
            
        }
        s.close();
    }
}