题解 | #删除有序链表中重复的元素-II#

/*
 * function ListNode(x){
 *   this.val = x;
 *   this.next = null;
 * }
 */
/**
 * 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
 *
 * 
 * @param head ListNode类 
 * @return ListNode类
 */
function deleteDuplicates( head ) {
    // write code here
    let arr = []
    let repeatArr = []
    let p1 = head
    while(p1) {
        if (arr.indexOf(p1.val) === -1) {
            arr.unshift(p1.val)
        }
        else {
            repeatArr.unshift(p1.val)
        }
        p1 = p1.next
    }
    let p2 = new ListNode(1001)
    let top = p2
    p2.next = head
    let left = p2
    while(p2) {
        if (repeatArr.indexOf(p2.val) !== -1) {
            left.next = p2.next
        }
        else {
            left = p2
        }
        
        p2 = p2.next
    }
    return top.next
}
module.exports = {
    deleteDuplicates : deleteDuplicates
};