链表的基本操作（单向，不循环，不带头）

class Node5{
public int data;
public Node5 next;

public  Node5 (int data){
    this.data = data;
}

}
public class MyTryTry {
public Node5 head ;
//头插入；
public void addFrist(int data){
Node5 node = new Node5(data);
node .next = this .head;
this.head = node;
}
//打印链表
public void disPlay (){
Node5 cur = this.head;
while (cur != null){
System.out.print( cur.data + " ");
cur = cur.next;
}
System.out.println();
}
//尾插入
public void addLast(int data){
Node5 node = new Node5(data);
if(this.head == null){
addFrist(data);
return;
}
Node5 cur = this.head;
while (cur.next != null){
cur = cur.next;
}
cur.next = node;
}
//打印链表长度
public int size(){
int count = 0;
Node5 cur = this.head;
while (cur != null){
count ++;
cur = cur.next;
}
return count ;
}
//任意位置插入元素
public void addIndex (int index , int data){
Node5 note = new Node5(data);
if (index < 0 || index > this.size()){
System.out.println(“插入错误”);
return;
}
if (index == 0){
addFrist(data);
}
Node5 cur = reaschPrev(index);
note.next = cur .next;
cur.next = note;
}
// 寻找插入数字的节点；
public Node5 reaschPrev( int index){
Node5 cur = this.head;
int count = 0;
while (count < index - 1){
cur = cur.next;
count ++ ;
}
return cur;
}
//寻找关键字key是否存在；
public boolean contains(int key){
Node5 cur = this.head;
while (cur != null){
if (cur.data == key){
return true;
}
cur = cur.next;
}
return false;
}
//删除第一个关键字key
public void reMove(int key){
if(this.head.data == key){
this.head = this.head.next;//删除头数字，这个数字的next就是ta的头
return;
}
Node5 cur = reasechPrmv2(key);
if(cur == null){
return;
}
Node5 asc = cur.next;
cur.next = asc.next;
}
//寻找key的前驱
public Node5 reasechPrmv2(int key){
Node5 cur = this.head;
while (cur.next != null){
if (cur.next.data == key){
return cur;
}
cur = cur.next;
}
return null;
}
public static void main (String[] args){
MyTryTry myTryTry = new MyTryTry();
myTryTry.addFrist(1);
myTryTry.addFrist(4);
myTryTry.addFrist(5);
myTryTry.disPlay();
myTryTry.addLast(6);
myTryTry.addLast(9);
myTryTry.disPlay();
System.out.println(myTryTry.size());
myTryTry.addIndex(3,5);
myTryTry.addIndex(0,7);
myTryTry.addIndex(10,5);
myTryTry.disPlay();
System.out.println(myTryTry.contains(10));
System.out.println(myTryTry.contains(9));
myTryTry.reMove(9);
myTryTry.reMove(5);
myTryTry.reMove(20);
myTryTry.disPlay();
}
}