Reverse a linked list
Given the head of a singly linked list, reverse the list, and return the reversed list.
public ListNode reverseList(ListNode head) {
/* iterative solution */
ListNode newHead = null;
while (head != null) {
ListNode next = head.next;
head.next = newHead;
newHead = head;
head = next;
}
return newHead;
}
public ListNode reverseList(ListNode head) {
/* recursive solution */
return reverseListInt(head, null);
}
private ListNode reverseListInt(ListNode head, ListNode newHead) {
if (head == null)
return newHead;
ListNode next = head.next;
head.next = newHead;
return reverseListInt(next, head);
}
Posted by Jamie Meyer a month ago