Package g0101_0200.s0143_reorder_list

Class Solution

  • All Implemented Interfaces:
    
public final class Solution

    143 - Reorder List.

    Medium

    You are given the head of a singly linked-list. The list can be represented as:

    L<sub>0</sub> → L<sub>1</sub> → … → L<sub>n - 1</sub> → L<sub>n</sub>

    Reorder the list to be on the following form:

    L<sub>0</sub> → L<sub>n</sub> → L<sub>1</sub> → L<sub>n - 1</sub> → L<sub>2</sub> → L<sub>n - 2</sub> → …

    You may not modify the values in the list's nodes. Only nodes themselves may be changed.

    Example 1:

    Input: head = 1,2,3,4

    Output: 1,4,2,3

    Example 2:

    Input: head = 1,2,3,4,5

    Output: 1,5,2,4,3

    Constraints:

    • The number of nodes in the list is in the range <code>1, 5 * 10<sup>4</sup></code>.

    • 1 &lt;= Node.val &lt;= 1000

    • Nested Class Summary

      Nested Classes 
      Modifier and Type Class Description

    • Field Summary

      Fields 
      Modifier and Type Field Description

    • Constructor Summary

      Constructors 
      Constructor Description
      Solution()

    • Enum Constant Summary

      Enum Constants 
      Enum Constant Description

    • Method Summary

      Modifier and Type Method Description
      final Unit reorderList(ListNode head)

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait