2018.04.03 1st Semester 한양대 에리카 자료구조 과제 DoublyLinkedList

목표

코드

// Made By TheKinGoD

import java.util.*;

public class DoublyLinkedList {

    private static class Node<String> {
        private String element;
        private Node<String> prev;
        private Node<String> next;
        public Node(String e, Node<String> p, Node<String> n) {
            element = e; prev = p; next = n;
        }
        public String getElement() { return element; }
        public Node<String> getPrev() { return prev; }
        public Node<String> getNext() { return next; }
        public void setPrev(Node<String> p) { prev = p; }
        public void setNext(Node<String> n) { next = n; }
    }

    private static Node<String> header;
    private static Node<String> trailer;
    private static int size = 0;

    public static int size() { return size; }
    public static boolean isEmpty() { return size == 0; }

    public static String first( ) {
        if (isEmpty()) return null;
        return header.getNext().getElement();
    }

    public static String last( ) {
        if (isEmpty()) return null;
        return trailer.getPrev().getElement();
    }

    public static void addFirst(String e) {
        addBetween(e, header, header.getNext());
    }

    public static void addLast(String e) {
        addBetween(e, trailer.getPrev(), trailer);
    }

    public static String removeFirst( ) {
        if (isEmpty()) return null;
        return remove(header.getNext());
    }

    public static String removeLast( ) {
        if (isEmpty()) return null;
        return remove(trailer.getPrev());
    }

    private static void addBetween(String e, Node<String> predecessor, Node<String> successor) {
        Node<String> newest = new Node<>(e, predecessor, successor);
        predecessor.setNext(newest);
        successor.setPrev(newest);
        size++;
    }

    private static String remove(Node<String> node) {
        Node<String> predecessor = node.getPrev( );
        Node<String> successor = node.getNext( );
        predecessor.setNext(successor);
        successor.setPrev(predecessor);
        size--;
        return node.getElement( );
    }

    public static void PrintAll(){
        if (isEmpty()) {
            System.out.println("No Element in List!");
            return;
        }
        System.out.println("------------------------------------------------");
        Node<String> tmp = header;
        for(int i = 0; i < size(); i++){
            tmp = tmp.getNext();
            System.out.println("DoublyLinkedList[" + i + "] = " + tmp.getElement());
        }
    }

    public static String removing(int idx){
        if (idx < 0 || idx > size() - 1) {
            System.out.println("Over/UnderFlow!");
            return null;
        }
        Node<String> tmp = header;
        for(int i = 0; i <= idx; i++){
            tmp = tmp.getNext();
        }
        remove(tmp);
        return tmp.getElement();
    }

    public static void insertion(int idx, String e){
        if (idx > size() || idx < 0) {
            System.out.println("Over/UnderFlow!");
            return;
        }
        Node<String> tmp = header;
        for(int i = 0; i < idx; i++){
            tmp = tmp.getNext();
        }
        addBetween(e, tmp, tmp.getNext());
    }

    public static void main(String[] args) {
        header = new Node<>(null, null, null);
        trailer = new Node<>(null, header, null);
        header.setNext(trailer);
        Scanner sc = new Scanner(System.in);
        while (true) {
            System.out.println("------------------------------------------------");
            System.out.println("0 = End, 1 = Insert, 2 = Removing, 3 = Print All");
            System.out.println("------------------------------------------------");
            System.out.print("Case : ");
            int Case = sc.nextInt();
            if (Case == 0){
                System.out.println("Program is END!");
                break;
            }
            else if (Case == 1){
                System.out.print("String : ");
                String text = sc.next();
                System.out.print("Index : ");
                int idx = sc.nextInt();
                insertion(idx, text);
            }
            else if (Case == 2){
                System.out.print("Index : ");
                int idx = sc.nextInt();
                removing(idx);
            }
            else {
                PrintAll();
            }
        }
    }
}

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파일

DoublyLinkedList.java