题解 | #重排链表#

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

function nextNode (len, node) {
    
}

/**
 * 
 * @param head ListNode类 
 * @return void
 */
function reorderList( head ) {
    if (head === null) return head
    let node = head
    
    while (node !== null && node.next !== null && node.next.next !== null) {
        let tempNode1 = node
        while (tempNode1.next !== null) {
            tempNode1 = tempNode1.next
        }
        
        let temp1 = node.next, temp2 = temp1
        while (temp2 !== null && temp2.next !== null) {
            if (tempNode1 === temp2.next) {
                temp2.next = null
                break
            }
            temp2 = temp2.next
        }
        tempNode1.next = temp1
        node.next = tempNode1
        
        node = node.next.next
    }
    
    return node
}
module.exports = {
    reorderList : reorderList
};