[Algorithm] 38 week(10.17 ~ 10.23) 3/3

328. Odd Even Linked List

var oddEvenList = function(head) {
    if(!head) return head;

    let odd = head;
    let even = head.next;
    let even_head = head.next;

    while(even && even.next){
        odd.next = odd.next.next;
        even.next = even.next.next;

        odd = odd.next;
        even = even.next;
    }

    odd.next = even_head;
    return head;
};