链表的反转

`package class03.yumx03;

public class Code1_ReverseList {

public static Node reverseNode(Node head) {
Node pre = null;
Node next;
while (head != null) {
next = head.next;
head.next = pre;
pre = head;
head = next;
}

return pre;
}

public static DoubleNode reverseDoubleNode(DoubleNode head) {
DoubleNode pre = null;
DoubleNode next;
while (head != null) {
next = head.next;
head.next = pre;
head.pre = next;
pre = head;
head = next;
}
return pre;
}
}

class Node {
public Integer value;

public Node next;

public Node(Integer value) {
this.value = value;
}
}

class DoubleNode {
public Integer value;
public DoubleNode pre;
public DoubleNode next;

public DoubleNode(Integer value) {
this.value = value;
}
}
`