86. Partition List

public static ListNode partition(ListNode head, int x) {        if(head == null) {            return head;        }        ListNode mhead = null,shead = null,scur =null, mcur = null,cur = head;        while(cur != null) {            if(cur.val < x) {                if(mhead == null) {                    mhead = cur;                    mcur = cur;                }else {                    mcur.next = cur;                    mcur = cur;                }            }else {                if(shead == null) {                    shead = cur;                    scur = cur;                }else {                    scur.next = cur;                    scur = cur;                }            }            cur = cur.next;        }        if(scur != null) {            scur.next =null;        }        if(mcur != null) {            mcur.next = shead;        }else {            mhead = shead;        }        return mhead;    }