public static void main(String[] args) {
PartitionList pl = new PartitionList();
ListNode l1 = new ListNode(1);
ListNode l2 = new ListNode(4);
ListNode l3 = new ListNode(3);
ListNode l4 = new ListNode(2);
ListNode l5 = new ListNode(5);
ListNode l6 = new ListNode(2);
l1.next = l2;
l2.next = l3;
l3.next = l4;
l4.next = l5;
l5.next = l6;
ListNode rtlist = pl.partition(l1, 3);
while (rtlist != null) {
System.out.println(rtlist.val);
rtlist = rtlist.next;
}
}
public ListNode partition(ListNode head, int x) {
// write your code here
if (head == null) return head;
ListNode greater = new ListNode(0);
ListNode less = new ListNode(0);
ListNode ptr = head;
ListNode lp = less;
ListNode gp = greater;
while (ptr != null) {
if (ptr.val < x) {
lp.next = ptr;
lp = lp.next;
} else {
gp.next = ptr;
gp = gp.next;
}
ptr = ptr.next;
}
lp.next = greater.next;
gp.next = null;
return less.next;
}