无头结点的单链表（java实现）

import java.util.Random;

class Node {

int data;

Node next;

Node(int data) {

this.data = data;

next = null;

}

}

class List {

Node first = null;

List(int n) {

Random rand = new Random(96);

for (int i = 0; i < n; i++) {

insert(rand.nextInt() %100);

}

}

public void insert(int data) {

Node node = new Node(data);

Node tmp;

if (first == null) {

first = node;

return;

}

if (first.data < data) {

node.next = first;

first = node;

return;

}

tmp = first;

while (tmp.next != null) {

if (data > tmp.next.data)

break;

tmp = tmp.next;

}

node.next = tmp.next;

tmp.next = node;

}

public void delete(int data) {

Node tmp;

if (data == first.data) {

first = first.next;

return;

}

tmp = first;

while (tmp.next != null) {

if (data == tmp.next.data) {

tmp.next = tmp.next.next;

return;

}

tmp = tmp.next;

}

}

public void reverse1(){

Node pre, cur, last;

pre = null;

cur = first;

while (cur != null) {

last = cur.next;

cur.next = pre;

pre = cur;

cur = last;

}

first = pre;

}

public void reverse2(){

Node cur, last;

cur = first;

if (cur == null || cur.next == null)

return;

while (cur.next.next != null)

cur = cur.next;

last = cur.next;

cur.next = null;

reverse2();

last.next = cur;

first = last;

}

public void reverse3() {

Node cur, last;

cur = first;

if(cur == null || cur.next == null)

return;

last = cur.next;

first = last;

reverse3();

last.next = cur;

cur.next = null;

}

public void show() {

Node tmp;

tmp = first;

while (tmp != null) {

System.out.print(tmp.data + " ");

tmp = tmp.next;

}

System.out.println();

}

}