LC-206 reverse Linked List

In linked list using variables like prev, curt, next are more meaningful.

//iterative way
public class Solution {
    public ListNode reverseList(ListNode head) {
        if (head == null) {
            return null;
        }
        
        ListNode prev = null;
        ListNode curt = head;
        // 1 ->   2   ->3
        // prev  curt   
        // 1 <- 2     3
        //     prev  curt
        while (curt != null) {
            ListNode temp = curt.next;
            curt.next = prev;
            prev = curt;
            curt = temp;
        }
        return prev;
    }
}

//recursion way
public class Solution {
    public ListNode reverseList(ListNode head) {
    /* recursive solution */
    return reverseListInt(head, null);
    }

    private ListNode reverseListInt(ListNode curt, ListNode prev) {
        if (curt == null)
            return prev;
        ListNode next = curt.next;
        curt.next = prev;
        return reverseListInt(next, curt);
    }
}