JZ15 反转链表

/*function ListNode(x){
    this.val = x;
    this.next = null;
}*/
function ReverseList(pHead)
{
    // write code here
    if(!pHead)return pHead;
    let prev = null;
    while(pHead) {
        let curr = pHead
        pHead = pHead.next
        curr.next = prev
        prev = curr
    }
    return prev
}
module.exports = {
    ReverseList : ReverseList
};