package com.coding.basic;
public class LinkedList implements List {
private Node head = null;
private int size = 0;
public LinkedList() {
this.head = new Node();
this.head.next = null;
this.head.data = null;
this.size = 0;
}
public void add(Object o) {
if (null == o) {
return;
}
Node next = new Node();
next.data = o;
next.next = null;
/**
* 寻找尾部节点
*/
Node p = head;
while (p.next != null) {
p = p.next;
}
p.next = next;
size++;
}
public void add(int index, Object o) {
if (index < 0 || index > size) {
throw new IndexOutOfBoundsException();
}
if (null == o) {
return;
}
Node next = new Node();
next.data = o;
next.next = null;
Node p = head.next;
Node pre = head;
int pos = 0;
while (p != null && pos < index) {
pre = p;
p = p.next;
pos++;
}
next.next = p;
pre.next = next;
size++;
}
public Object get(int index) {
if (index < 0 || index >= size) {
throw new IndexOutOfBoundsException();
}
Node p = head.next;
int pos = 0;
while (p != null && pos < index) {
p = p.next;
pos++;
}
return p == null ? null : p.data;
}
public Object remove(int index) {
if (index < 0 || index >= size) {
throw new IndexOutOfBoundsException();
}
Node p = head.next;
Node pre = p;
int pos = 0;
while (p != null && pos < index) {
pre = p;
p = p.next;
pos++;
}
Object o = p.data;
pre.next = p.next;
size--;
return o;
}
public int size() {
return size;
}
public void addFirst(Object o) {
if (null == o) {
return;
}
Node next = new Node();
next.next = null;
next.data = o;
next.next = head.next;
head.next = next;
size++;
}
public void addLast(Object o) {
if (null == o) {
return;
}
Node p = head;
while (p.next != null) {
p = p.next;
}
Node next = new Node();
next.data = o;
next.next = null;
p.next = next;
size++;
}
public Object removeFirst() {
if (size <= 0) {
throw new IndexOutOfBoundsException();
}
Node p = head.next;
Object o = p.data;
head.next = p.next;
size--;
return o;
}
public Object removeLast() {
if (size <= 0) {
throw new IndexOutOfBoundsException();
}
Node p = head.next;
Node pre = head;
while (p.next != null) {
pre = p;
p = p.next;
}
Object o = p.data;
pre.next = p.next;
size--;
return o;
}
public Iterator iterator() {
return new Iterator() {
Node current = head;
@Override
public Object next() {
Object o = current.next.data;
current = current.next;
return o;
}
@Override
public boolean hasNext() {
return current.next != null;
}
};
}
private static class Node {
Object data;
Node next;
}
/**
* 把该链表逆置 例如链表为 3->7->10 , 逆置后变为 10->7->3
*/
public void reverse() {
Node p = head.next.next;
Node pre = head.next;
pre.next = null;
while (p != null) {
Node pp = p.next;
p.next = pre;
pre = p;
p = pp;
}
head.next = pre;
// --- --- ---
}
/**
* 删除一个单链表的前半部分 例如：list = 2->5->7->8 , 删除以后的值为 7->8 如果list = 2->5->7->8->10
* ,删除以后的值为7,8,10
*
*/
public void removeFirstHalf() {
}
/**
* 从第i个元素开始， 删除length 个元素 ， 注意i从0开始
*
* @param i
* @param length
*/
public void remove(int i, int length) {
}
/**
* 假定当前链表和listB均包含已升序排列的整数 从当前链表中取出那些listB所指定的元素 例如当前链表 =
* 11->101->201->301->401->501->601->701 listB = 1->3->4->6
* 返回的结果应该是[101,301,401,601]
*
* @param list
*/
public int[] getElements(LinkedList list) {
return null;
}
/**
* 已知链表中的元素以值递增有序排列，并以单链表作存储结构。 从当前链表中中删除在listB中出现的元素
*
* @param list
*/
public void subtract(LinkedList list) {
}
/**
* 已知当前链表中的元素以值递增有序排列，并以单链表作存储结构。 删除表中所有值相同的多余元素（使得操作后的线性表中所有元素的值均不相同）
*/
public void removeDuplicateValues() {
}
/**
* 已知链表中的元素以值递增有序排列，并以单链表作存储结构。 试写一高效的算法，删除表中所有值大于min且小于max的元素（若表中存在这样的元素）
*
* @param min
* @param max
*/
public void removeRange(int min, int max) {
}
/**
* 假设当前链表和参数list指定的链表均以元素依值递增有序排列（同一表中的元素值各不相同）
* 现要求生成新链表C，其元素为当前链表和list中元素的交集，且表C中的元素有依值递增有序排列
*
* @param list
*/
public LinkedList intersection(LinkedList list) {
return null;
}
public static void main(String[] args) {
LinkedList list = new LinkedList();
list.add("A");
list.add("B");
list.add("C");
list.add("D");
list.reverse();
Iterator it = list.iterator();
while (it.hasNext()) {
Object o = it.next();
System.out.println(o);
}
}
}