OddEvenPairs APS 2019 kol 1

import java.io.IOException;
import java.util.Scanner;

class SLLNode<E> {
    protected E element;
    protected SLLNode<E> succ;
    public SLLNode(){
        this.succ = null;
    }
    public SLLNode(E elem, SLLNode<E> succ) {
        this.element = elem;
        this.succ = succ;
    }
    public SLLNode(E element){
        this.element = element;
        this.succ = null;
    }

    @Override
    public String toString() {
        return element.toString();
    }
}
class SLL<E> {
    private SLLNode<E> first;

    public SLL() {
        // Construct an empty SLL
        this.first = null;
    }

    public void deleteList() {
        first = null;
    }

    public int length() {
        int ret;
        if (first != null) {
            SLLNode<E> tmp = first;
            ret = 1;
            while (tmp.succ != null) {
                tmp = tmp.succ;
                ret++;
            }
            return ret;
        } else
            return 0;

    }

    @Override
    public String toString() {
        String ret = new String();
        if (first != null) {
            SLLNode<E> tmp = first;
            ret += tmp + "->";
            while (tmp.succ != null) {
                tmp = tmp.succ;
                ret += tmp + "->";
            }
        } else
            ret = "Prazna lista!!!";
        return ret;
    }

    public void insertFirst(E o) {
        SLLNode<E> ins = new SLLNode<E>(o, first);
        first = ins;
    }

    public void insertAfter(E o, SLLNode<E> node) {
        if (node != null) {
            SLLNode<E> ins = new SLLNode<E>(o, node.succ);
            node.succ = ins;
        } else {
            System.out.println("Dadenot jazol e null");
        }
    }

    public void insertBefore(E o, SLLNode<E> before) {

        if (first != null) {
            SLLNode<E> tmp = first;
            if (first == before) {
                this.insertFirst(o);
                return;
            }
            //ako first!=before
            while (tmp.succ != before)
                tmp = tmp.succ;
            if (tmp.succ == before) {
                SLLNode<E> ins = new SLLNode<E>(o, before);
                tmp.succ = ins;
            } else {
                System.out.println("Elementot ne postoi vo listata");
            }
        } else {
            System.out.println("Listata e prazna");
        }
    }

    public void insertLast(E o) {
        if (first != null) {
            SLLNode<E> tmp = first;
            while (tmp.succ != null)
                tmp = tmp.succ;
            SLLNode<E> ins = new SLLNode<E>(o, null);
            tmp.succ = ins;
        } else {
            insertFirst(o);
        }
    }

    public E deleteFirst() {
        if (first != null) {
            SLLNode<E> tmp = first;
            first = first.succ;
            return tmp.element;
        } else {
            System.out.println("Listata e prazna");
            return null;
        }
    }

    public E delete(SLLNode<E> node) {
        if (first != null) {
            SLLNode<E> tmp = first;
            if (first == node) {
                return this.deleteFirst();
            }
            while (tmp.succ != node && tmp.succ.succ != null)
                tmp = tmp.succ;
            if (tmp.succ == node) {
                tmp.succ = tmp.succ.succ;
                return node.element;
            } else {
                System.out.println("Elementot ne postoi vo listata");
                return null;
            }
        } else {
            System.out.println("Listata e prazna");
            return null;
        }

    }

    public SLLNode<E> getFirst() {
        return first;
    }

    public SLLNode<E> getLast(){
        SLLNode<E> temp = first;
        while (temp.succ!=null){
            temp = temp.succ;
        }
        return temp;
    }

    public SLLNode<E> find(E o) {
        if (first != null) {
            SLLNode<E> tmp = first;
            while (tmp.element != o && tmp.succ != null)
                tmp = tmp.succ;
            if (tmp.element == o) {
                return tmp;
            } else {
                System.out.println("Elementot ne postoi vo listata");
            }
        } else {
            System.out.println("Listata e prazna");
        }
        return first;
    }

    public void printList(){
        SLLNode<E> temp = first;
        while (temp!=null){
            System.out.println(temp.element);
            temp = temp.succ;
        }
    }

}
public class ImeNaKlasa {
    public static SLL oddEvenPairsFunction(SLL<Integer>list){
        SLLNode<Integer> temp = list.getFirst();
        SLLNode<Integer> oddTemp = new SLLNode<Integer>();
        SLLNode<Integer> evenTemp = new SLLNode<Integer>();
        int nEven = 0, nOdd = 0;
        int paren = 0, neparen = 0;
        while (temp != null){
            if ( temp.element%2 == 0 ){
                nEven++;
                if ( nEven == 1 ){
                    paren = temp.element;
                    evenTemp = temp;
                }
                if ( nEven == 2 ){
                    nEven = 0;
                    SLLNode<Integer> newNode = new SLLNode<Integer>(temp.element+paren);
                    newNode.succ = evenTemp.succ;
                    evenTemp.succ = newNode;
                    list.delete(evenTemp);
                    list.delete(temp);
                }
            }
            else{
                nOdd++;
                if ( nOdd == 1){
                    neparen = temp.element;
                    oddTemp = temp;
                }
                if ( nOdd == 2 ){
                    nOdd = 0;
                    SLLNode<Integer> newNode = new SLLNode<Integer>(neparen-temp.element);
                    newNode.succ = oddTemp.succ;
                    oddTemp.succ = newNode;
                    list.delete(oddTemp);
                    list.delete(temp);
                }
            }
            temp = temp.succ;
        }



        return list;
    }

    public static void main(String []args) throws IOException {
        SLL<Integer> list = new SLL<Integer>();
        Scanner scanner = new Scanner(System.in);
        int n = scanner.nextInt();
        for (int i =0 ; i < n; i++){
            list.insertLast(scanner.nextInt());
        }
        oddEvenPairsFunction(list);
        list.printList();
    }
}