题解 | #删除有序链表中重复的元素-II#

 * function ListNode(x){
 *   this.val = x;
 *   this.next = null;
 * }
 */

/**
  * 
  * @param head ListNode类 
  * @return ListNode类
  */
function deleteDuplicates( head ) {
    // write code here
    if(!head || !head.next){
        return head
    }
    let res = new ListNode(0)
    res.next = head
    let cur = res
    while(cur.next != null && cur.next.next != null){
        if(cur.next.val === cur.next.next.val){
            let val = cur.next.val
            while(cur.next && cur.next.val == val){
                cur.next = cur.next.next
            }
        }else{
            cur = cur.next
        }
    }
    return res.next
}
module.exports = {
    deleteDuplicates : deleteDuplicates
};