Cacher is the code snippet organizer for pro developers

# Definition for singly-linked list.
# class ListNode(object):
#     def __init__(self, x):
#         self.val = x
#         self.next = None

class Solution(object):
    def partition(self, head, x):
        """
        :type head: ListNode
        :type x: int
        :rtype: ListNode
        """
        dummy1 = ListNode(0)
        dummy2 = ListNode(0)
        p1 = dummy1
        p2 = dummy2
        p = head
        while p:
            if p.val < x:
                p1.next = p
                p1 = p1.next
                p = p.next
                p1.next = None
                # If you are merging two lists, then you don't have to do that.
                # but if you are doing in one list, you have to do set None to the last node.
                # Otherwise, there will be a loop, `node1(p1)->node2(p2)`.
            else:
                p2.next = p
                p2 = p2.next
                p = p.next
                p2.next = None
        p1.next = dummy2.next
        return dummy1.next