package com.byhieg.coding2017.homework312;
import com.byhieg.coding2017.homework226.Iterator;
import com.byhieg.coding2017.homework226.List;
import com.byhieg.utils.bprint.FullPrint;
public class LinkedList implements List {
private Node head;
int size = 0;
public void add(Object o) {
addLast(o);
}
public void add(int index, Object o) {
checkRangeForAdd(index);
if (index == size) {
addLast(o);
return;
}
Node nextNode = node(index);
Node newNode = new Node(o, nextNode);
Node prevNode;
if (index == 0) {
prevNode = null;
} else {
prevNode = node(index - 1);
}
if (prevNode == null) {
head = newNode;
} else {
prevNode.next = newNode;
}
size++;
}
private Node node(int index) {
Node cursor = head;
for (int i = 0; i < index; i++) {
cursor = cursor.next;
}
return cursor;
}
private void checkRangeForAdd(int index) {
if (index > size || index < 0) {
throw new IndexOutOfBoundsException("指定的index超过界限");
}
}
public Object get(int index) {
checkRange(index);
return node(index).data;
}
private void checkRange(int index) {
if (index >= size || index < 0) {
throw new IndexOutOfBoundsException("指定index超过界限");
}
}
public Object remove(int index) {
checkRange(index);
Node targetNode = node(index);
Object o = targetNode.data;
Node prevNode;
Node nextNode = targetNode.next;
if (index == 0) {
prevNode = null;
} else {
prevNode = node(index - 1);
}
if (prevNode == null) {
head = nextNode;
targetNode.next = null;
} else {
prevNode.next = nextNode;
targetNode.next = null;
}
targetNode.data = null;
size--;
return o;
}
public int size() {
return size;
}
public void addFirst(Object o) {
Node nextNode = head;
Node newNode = new Node(o, nextNode);
head = newNode;
size++;
}
public void addLast(Object o) {
Node newNode = new Node(o, null);
if (size == 0) {
head = newNode;
} else {
Node lastNode = node(size - 1);
lastNode.next = newNode;
}
size++;
}
public Object removeFirst() {
return remove(0);
}
public Object removeLast() {
return remove(size() - 1);
}
public Iterator iterator() {
return new MyIterator();
}
private class MyIterator implements Iterator {
public Node cursor = head;
@Override
public boolean hasNext() {
return cursor != null;
}
@Override
public Object next() {
Object o = cursor.data;
cursor = cursor.next;
return o;
}
}
private static class Node {
Object data;
Node next;
public Node(Object data, Node next) {
this.data = data;
this.next = 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() {
for (int i = 0; i < size() / 2; i++) {
if (i == 0) {
Object o1 = remove(i);
Object o2 = remove(size - i - 1);
addFirst(o2);
addLast(o1);
} else {
Object o1 = remove(i);
Object o2 = remove(size - i - 1);
add(i, o2);
add(size - i, o1);
}
}
}
/**
* 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() {
for (int i = 0; i < size() / 2; i++) {
remove(0);
}
}
/**
* 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) {
for (int j = 0 ; j < length ;j ++) {
remove(i);
}
}
/**
* 假定当前链表和list均包含已升序排列的整数
* 从当前链表中取出那些list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) {
int[] result = new int[list.size()];
int count = 0;
for (int i = 0 ; i < list.size();i++) {
result[count++] = (int)get((Integer) list.get(i));
}
return result;
}
/**
* 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list中出现的元素
*
* @param list
*/
public void subtract(LinkedList list) {
for (int i = 0 ; i < list.size();i++) {
for (int j = 0 ;j < size();j++) {
if (list.get(i) == get(j)) {
remove(j);
}
}
}
}
/**
* 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() {
for (int i = 0; i < size();i++) {
for (int j = i + 1 ; j < size();j++) {
if (get(i) == get(j)){
remove(j);
}
}
}
}
/**
* 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) {
for (int i = 0 ; i < size();i++) {
if ((int)get(i) > min && (int)get(i) < max){
remove(i);
i--;
}
}
}
/**
* 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) {
LinkedList result = new LinkedList();
for (int i = 0 ; i < size();i++) {
for (int j = 0 ; j < list.size();j++){
if (get(i) == list.get(j)){
result.add(get(i));
}
}
}
return result;
}
}