目录
1.扑克牌游戏
2.链表基本功能的实现(单项链表)
3.移除链表元素力扣
4.反转链表力扣
5.链表的中间结点
5.返回倒数第k个节点编辑
6.合并两个有序链表
7.链表基本功能的实现(双向链表)
8.链表分割
1.扑克牌游戏
public class Card {private String suit;private int rank;public Card( int rank,String suit) {this.suit = suit;this.rank = rank;}@Overridepublic String toString() {return"{"+suit+rank+"} ";}
}
import java.util.ArrayList;
import java.util.List;
import java.util.Random;public class CardDemo {public static final String[] stuits={"♠","方块","♥","♣"};public List<Card> buyCard() {List<Card> cardList = new ArrayList<>();for (int i = 0; i < 13; i++) {for (int j = 0; j < 4; j++) {int rank = i;String suit = stuits[j];Card card = new Card(rank,suit);cardList.add(card);}}return cardList;}public void shuffle(List<Card> cardList){Random random = new Random();for (int i =cardList.size()-1; i > 0; i--) {int index = random.nextInt(i);swap(cardList,i,index);}}private void swap (List<Card>cardList,int i,int j){Card tmp = cardList.get(i);cardList.set(i,cardList.get(j));cardList.set(j,tmp);}public List<List<Card>> play(List<Card>cardList){List<Card> hand0 = new ArrayList<>();List<Card> hand1 = new ArrayList<>();List<Card> hand2 = new ArrayList<>();List<List<Card>> hand = new ArrayList<>();hand.add(hand0);hand.add(hand1);hand.add(hand2);for (int i = 0; i < 5; i++) {for (int j = 0; j < 3; j++) {Card card = cardList.remove(0);hand.get(j).add(card);}}return hand;}
}
import java.util.List;public class Test {public static void main(String[] args) {//买牌CardDemo cardDemo = new CardDemo();List<Card> cardList = cardDemo.buyCard();System.out.println(cardList);//洗牌cardDemo.shuffle(cardList);//轮流发牌List <List<Card>> ret = cardDemo.play(cardList);for (int i = 0; i < ret.size(); i++) {System.out.println("第"+(i+1)+"个人的牌"+ret.get(i));}}
}
2.链表基本功能的实现(单项链表)
public class Test {public static void main(String[] args) {MySingleList list = new MySingleList();list.CreatList();list.clear();list.display();}
}
public class MySingleList implements IList {static class ListNode{private int val;private ListNode next;public ListNode(int val){this.val = val;}}public ListNode head;public void CreatList(){ListNode node1 = new ListNode(12);ListNode node2 = new ListNode(12);ListNode node3 = new ListNode(23);ListNode node4 = new ListNode(45);ListNode node5 = new ListNode(56);node1.next = node2;node2.next = node3;node3.next = node4;node4.next = node5;this.head = node1;}@Overridepublic void addFirst(int data) {ListNode node = new ListNode(data);node.next = head;head = node;}@Overridepublic void addLast(int data) {ListNode node = new ListNode(data);ListNode cur = head;if(head == null){head = node;return;}while(cur.next != null ){cur = cur.next;} cur.next = node;}@Overridepublic void addIndex(int index, int data) {int len = size();if(index < 0 || index > len){System.out.println("index位置不合法");return;}if( index == 0){addFirst(data);return;}if(index == len){addLast(data);return;}ListNode node = new ListNode(data);ListNode cur =head;while(index - 1 != 0){cur = cur.next;index--;}node.next = cur.next;cur.next = node;}@Overridepublic boolean contains(int key) {ListNode cur = head;while(cur != null){if(cur.val == key){return true;}elsecur = cur.next;}return false;}@Overridepublic void remove(int key) {if(head == null){return;}if(head.val == key){head = head.next;return;}ListNode cur = findNodeOfKey(key);if(cur == null){return;}cur.next = cur.next.next;}private ListNode findNodeOfKey(int key){ListNode cur = head;while(cur.next != null){if(cur.next.val == key){return cur;}cur = cur.next;}return null;}@Overridepublic void removeAllKey(int key) {if (head == null) {return;}ListNode pre = head;ListNode cur = head.next;while (cur != null) {if (cur.val == key) {pre.next = cur.next;cur = cur.next;} else {pre = cur;cur = cur.next;}}if (head.val == key){head = head.next;}}@Overridepublic int size() {ListNode cur = this.head;int len = 0;while(cur != null){len++;cur = cur.next;}System.out.println();return len;}@Overridepublic void clear() {ListNode cur = head;while(cur != null){ListNode curN = cur.next;cur.next = null;cur = curN;}head = null;}@Overridepublic void display() {ListNode cur = head;while ((cur != null)){System.out.print(cur.val+" ");cur = cur.next;}}
}
public interface IList {public void addFirst(int data);public void addLast(int data);public void addIndex(int index,int data);public boolean contains (int key);public void remove(int key);public void removeAllKey(int key);public int size();public void clear();public void display();}
3.移除链表元素力扣
public class Solution {public ListNode removeElements(ListNode head, int val) {if(head == null){return head;}ListNode pre = head;ListNode cur = head.next;while(cur != null){if(cur.val == val){pre.next = cur.next;cur = cur.next;}else{pre = cur;cur = cur.next;}}if(head.val == val){head = head.next;}return head;}}
4.反转链表力扣
/*** Definition for singly-linked list.* public class ListNode {* int val;* ListNode next;* ListNode() {}* ListNode(int val) { this.val = val; }* ListNode(int val, ListNode next) { this.val = val; this.next = next; }* }*/
class Solution {public ListNode reverseList(ListNode head) {if(head == null){return head;}ListNode cur = head.next;head.next = null;while(cur != null){ListNode curN = cur.next;cur.next = head;head = cur;cur = curN;}return head;}
}
5.链表的中间结点
/*** Definition for singly-linked list.* public class ListNode {* int val;* ListNode next;* ListNode() {}* ListNode(int val) { this.val = val; }* ListNode(int val, ListNode next) { this.val = val; this.next = next; }* }*/
class Solution {public ListNode middleNode(ListNode head) {if(head == null){return head;}ListNode fast = head;ListNode slow = head;while(fast != null && fast.next != null){fast = fast.next.next;slow = slow.next;}return slow;}
}
5.返回倒数第k个节点
/*** Definition for singly-linked list.* public class ListNode {* int val;* ListNode next;* ListNode(int x) { val = x; }* }*/
class Solution {public int kthToLast(ListNode head, int k) {if(head == null){return head.val;}ListNode fast = head;ListNode slow = head;int count = k - 1;while(count != 0){fast = fast.next;count--;}while(fast.next != null){fast = fast.next;slow = slow.next;}return slow.val;}
}
6.合并两个有序链表
/*** Definition for singly-linked list.* public class ListNode {* int val;* ListNode next;* ListNode() {}* ListNode(int val) { this.val = val; }* ListNode(int val, ListNode next) { this.val = val; this.next = next; }* }*/
class Solution {public ListNode mergeTwoLists(ListNode list1, ListNode list2) {ListNode newHead = new ListNode(-1);ListNode tmp = newHead;while(list1 != null && list2 != null){if(list1.val <= list2.val){tmp.next = list1;list1 = list1.next;tmp = tmp.next;}else{tmp.next = list2;tmp = tmp.next;list2 = list2.next;}}if(list1 != null){tmp.next = list1;}if(list2 != null){tmp.next = list2;}return newHead.next;}
}
7.链表基本功能的实现(双向链表)
public class test {public static MyLinkedList.ListNode mergeTwoLists(MyLinkedList.ListNode list1,MyLinkedList. ListNode list2) {MyLinkedList. ListNode newHead = new MyLinkedList.ListNode(-1);MyLinkedList. ListNode tmp = newHead;while(list1 != null && list2 != null){if(list1.val < list2.val){tmp.next = list1;list1 = list1.next;tmp = tmp.next;}else{tmp.next = list2;tmp = tmp.next;list2 = list2.next;}}if(list1 != null){tmp.next = list1;}if(list2 != null){tmp.next = list2;}return newHead.next;}public static void main(String[] args) {MyLinkedList myLinkedList = new MyLinkedList();myLinkedList.addLast(1);myLinkedList.addLast(5);myLinkedList.addLast(9);myLinkedList.addLast(21);myLinkedList.addLast(7);myLinkedList.addLast(21);MyLinkedList myLinkedList1 =new MyLinkedList();myLinkedList1.addLast(1);myLinkedList1.addLast(5);myLinkedList1.addLast(9);myLinkedList1.addLast(21);myLinkedList1.addLast(7);myLinkedList1.addLast(21);MyLinkedList.ListNode newHead = mergeTwoLists( myLinkedList.head,myLinkedList1.head);myLinkedList.display2(newHead);}
}
public class MyLinkedList implements IList{static class ListNode {public int val;public ListNode preV;public ListNode next;public ListNode(int val) {this.val = val;}}public ListNode head;public ListNode last;@Overridepublic void addFirst(int data) {ListNode cur = head;ListNode node = new ListNode(data);if(head.next == null){head = last = node;}else{node.next = cur;cur.preV = node;head = node;}}@Overridepublic void addLast(int data) {ListNode cur = head;ListNode node = new ListNode(data);if(head == null) {head = last = node;}else{last.next = node;node.preV = last;last = node;}}@Override//在指点位置增删元素public void addIndex(int index, int data) {int len = size();if(index < 0 || index > len ){System.out.println("不符合条件");return;}if(index == 0){addFirst(index);return;}if(index == len){addLast(data);return;}else{ListNode cur = findOfKey(index);ListNode node = new ListNode(data);node.next = cur;node.preV = cur.preV;cur.preV.next = node;cur.preV = node;}}private ListNode findOfKey(int index){ListNode cur = head;while(index != 0){cur = cur.next;index--;}return cur;}@Overridepublic boolean contains(int key) {ListNode cur = head;while(cur != null){if(cur.val == key){return true;}cur = cur.next;}return false;}@Overridepublic void remove(int key) {ListNode cur = head;while(cur != null) {if (cur.val == key) {if (cur == head) {head = head.next;if (head != null) {head.preV = null;}} else {cur.preV.next = cur.next;if ( cur.next == null) {last = last.preV;}else {cur.next.preV = cur.preV;}}}cur =cur.next;}}@Overridepublic void removeAllKey(int key) {ListNode cur = head;while(cur != null) {if (cur.val == key) {if (cur == head) {head = head.next;if (head != null) {head.preV = null;}}else {cur.preV.next = cur.next;if (cur.next == null) {last = last.preV;}cur.next.preV = cur.preV;}}cur = cur.next;}}@Overridepublic int size() {ListNode cur = head;int len = 0;while(cur != null){len++;cur = cur.next;}return len;}@Overridepublic void clear() {ListNode cur = head;if(cur != null){ListNode curN = cur.next;cur.preV = null;cur.next = null;cur = curN;}head = null;last = null;}@Overridepublic void display() {ListNode cur = head;while(cur != null){System.out.print(cur.val+" ");cur = cur.next;}System.out.println();}//在指定位置进行打印public void display2(ListNode newHead) {ListNode cur = head;while (cur != null) {System.out.print(cur.val + " ");cur = cur.next;}System.out.println();}public ListNode reverseList() {if(head == null){return head;}ListNode cur = head.next;head.next = null;while(cur != null){ListNode curN = cur.next;cur.next = head;head = cur;cur = curN;}return head;}}
public interface IList {public void addFirst(int data);public void addLast(int data);public void addIndex(int index,int data);public boolean contains (int key);public void remove(int key);public void removeAllKey(int key);public int size();public void clear();public void display();}
8.链表分割
import java.util.*;/*
public class ListNode {int val;ListNode next = null;ListNode(int val) {this.val = val;}
}*/
public class Partition {public ListNode partition(ListNode pHead, int x) {ListNode as = null;ListNode ae = null;ListNode bs = null;ListNode be = null;ListNode cur = pHead;while(cur != null){if(cur.val < x){if(as == null){as = ae = cur;}else{ae.next = cur;ae = ae.next;}}else{if(bs == null){bs = be =cur;}else{be.next = cur;be = be.next;}}cur = cur.next;}if(as == null){return bs;}ae.next = bs;if(bs != null){be.next = null;}return as;}}