FilesExpand file tree

 master

/

ReorderList.java

Copy path

Blame

More file actions

Blame

More file actions

Latest commit

 

History

History

History

32 lines (28 loc) · 863 Bytes

 master

/

ReorderList.java

Copy path

Top

File metadata and controls

• Code
• Blame

32 lines (28 loc) · 863 Bytes

Raw

Copy raw file

Download raw file

Open symbols panel

Edit and raw actions

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

public class ReorderList {

public void reorderList(ListNode head) {

if (head == null || head.next == null) return;

ListNode p1 = head;

ListNode p2 = head;

while (p2.next != null && p2.next.next != null) {

p1 = p1.next;

p2 = p2.next.next;

}

ListNode preMiddle = p1;

ListNode preCurrent = p1.next;

while (preCurrent.next != null) {

ListNode current = preCurrent.next;

preCurrent.next = current.next;

current.next = preMiddle.next;

preMiddle.next = current;

}

p1 = head;

p2 = preMiddle.next;

while (p1 != preMiddle) {

preMiddle.next = p2.next;

p2.next = p1.next;

p1.next = p2;

p1 = p2.next;

p2 = preMiddle.next;

}

}

}