JAVA初窥-DAY13
JAVA初窥-DAY13
-
- 两个链表的合成
- 两个链表的公共节点
- 无头双向不循环链表的实现
两个链表的合成
两个有序链表合成为一个有序链表：
public static MyList addList(MyList list1,MyList list2){
Node f =new Node(-1);
Node e =f;
if (list1==null&&list2==null){
return null;
}
for (;list1.head!=null && list2.head!=null;){
if (list1.head.val<list2.head.val){
e.next = list1.head;
e = list1.head;
list1.head = list1.head.next;
}else {
e.next = list2.head;
e = list2.head;
list2.head=list2.head.next;
}
}
if (list1.head==null){
e.next = list2.head;
}else {
e.next = list1.head;
}
list1.head = f.next;
return list1;
}
两个链表的公共节点
寻找两个链表的公共节点：
main函数
MyList list1 = new MyList();//链表1
MyList list2 = new MyList();//链表2
list1.addHead(11);
list2.addHead(22);
Node node = new Node(999);//创建公共节点
list1.lastNode().next=node;//得到list1的最后一个节点并让其next等于node
list2.lastNode().next=node;//得到list2的最后一个节点并让其next等于node
list1.addHead(11);
list1.addHead(11);
list1.addLast(888);//公共部分
list1.addLast(777);//公共部分
list1.addLast(666);//公共部分
list1.show();
list2.show();
System.out.println(MyList.publicNode(list1, list2).val);//输出公共节点的val值
相关方法函数
public static Node publicNode(MyList list1,MyList list2){
Node node = new Node(-1);
Node cur1 = list1.head;
Node cur2 = list2.head;
int i;
for (;cur1.next!=null && cur2.next!=null;){
cur1 = cur1.next;
cur2 = cur2.next;
}
if(cur1.next == null){
for (i=0;cur2.next != null;i++){
cur2=cur2.next;
}
cur1=list1.head;
cur2=list2.head;
for (;i>0;i--){
cur2 = cur2.next;
}
for (;cur1 !=cur2;){
cur1 = cur1.next;
cur2 = cur2.next;
}
}else {
for (i=0;cur1.next != null;i++){
cur1=cur1.next;
}
cur1=list1.head;
cur2=list2.head;
for (;i>0;i--){
cur1 = cur1.next;
}
for (;cur1 !=cur2;){
cur1 = cur1.next;
cur2 = cur2.next;
}
}
if (cur1 != cur2){
System.out.println("没有公共节点");
return node;
}
return cur1;
}
public Node lastNode(){
Node cur = this.head;
for (;cur.next != null;){
cur = cur.next;
}
return cur;
}
无头双向不循环链表的实现
main函数
public class Demo013 {
public static void main(String[] args) {
List list = new List();
list.addFirst(3);
list.addFirst(2);
list.show();
list.addLast(4);
list.addFirst(1);
list.show();
list.addIndex(4,99);
list.addIndex(0,99);
list.addIndex(3,99);
list.show();
System.out.println(list.listSize);
System.out.println("----------1----------");
list.contains(1);
list.remove(1);
list.show();
System.out.println("----------2----------");
list.removeAllKey(99);
list.show();
System.out.println("----------3----------");
list.clear();
list.addLast(1);
list.show();
}
}
节点及链表及功能
public class List {
public Node head;//头
public Node tail;//尾巴
public int listSize=0;
//头插法
public void addFirst(int data) {
Node node = new Node(data);
if(this.head == null){
this.head = node;
this.tail = node;
}else {
this.head.prev = node;
node.next =head;
this.head = this.head.prev;
}
listSize++;
}
//尾插法
public void addLast(int data) {
Node node = new Node(data);
if (this.tail == null){
this.tail = node;
this.head = node;
}else {
this.tail.next = node;
node.prev = this.tail;
this.tail = this.tail.next;
}
listSize++;
}
//任意位置插入,第一个数据节点为0号下标
public void addIndex(int index,int data){
Node node = new Node(data);
Node cur = this.head;
if (index<0||index>listSize){
System.out.println("位置不合法！！");
return;
}
if (index == 0){
this.head.prev = node;
node.next =head;
this.head = this.head.prev;
listSize++;
return;
}else if (index == listSize){
this.tail.next = node;
node.prev = this.tail;
this.tail = this.tail.next;
listSize++;
return;
}else {
for (; index != 0 ; ) {
cur = cur.next;
index--;
}
cur.prev.next = node;
node.prev = cur.prev;
node.next = cur;
cur.prev = node;
listSize++;
}
}
//查找是否包含关键字key是否在单链表当中
public boolean contains(int key){
Node cur = this.head;
for (;cur!=null;){
if (cur.val == key){
return true;
}
cur = cur.next;
}
return false;
}
//删除第一次出现关键字为key的节点
public void remove(int key){
Node cur = this.head.next;
for (;cur!=this.tail;){
if (cur.val == key){
cur.next.prev = cur.prev;
cur.prev.next = cur.next;
listSize--;
return;
}
cur = cur.next;
}
if (this.head.val == key){
this.head = this.head.next;
this.head.prev =null;
listSize--;
return;
}else if (this.tail.val == key){
this.tail = this.tail.prev;
this.tail.next =null;
listSize--;
return;
}
System.out.println("未找到要删除的节点，请重新确认！");
}
//删除所有值为key的节点
public void removeAllKey(int key){
Node cur = this.head.next;
int tmpSize = listSize;
for (;cur!=this.tail;){
if (cur.val == key){
cur.next.prev = cur.prev;
cur.prev.next = cur.next;
listSize--;
}
cur = cur.next;
}
if (this.head.val == key){
this.head = this.head.next;
this.head.prev=null;
listSize--;
}
if (this.tail.val == key){
this.tail = this.tail.prev;
this.tail.next = null;
listSize--;
}
if (tmpSize == listSize){
System.out.println("未找到要删除的节点，请重新确认！");
}else {
System.out.println("删除成功！");
}
}
public void show(){
Node cur = this.head;
for (;cur != null;){
System.out.print(cur.val+" ");
cur = cur.next;
}
System.out.println();
}
public void clear(){
this.head = null;
this.tail = null;
listSize = 0;
}
}
class Node {
public int val;
public Node prev;
public Node next;
public Node(int val) {
this.val = val;
}
}