Given the head of a linked list and a value x, partition it such that all nodes less than x come before nodes greater than or equal to x.

You should preserve the original relative order of the nodes in each of the two partitions.

Example 1:

partition

  • Input: head = [1,4,3,2,5,2], x = 3
  • Output: [1,2,2,4,3,5]

Example 2:

  • Input: head = [2,1], x = 2
  • Output: [1,2]

Constraints:

  • The number of nodes in the list is in the range [0, 200].
  • -100 <= Node.val <= 100
  • -200 <= x <= 200