public static void reverseIterative(_<ListNode> list){ if( list.value() == null) return ; ListNode prev = null ; ListNode curr = list.value() ; while( curr!=null){ ListNode next = curr.next ; curr.next = prev ; prev = curr ; curr = next ; } list.set(prev); }
public static void reverseRecursive(_<ListNode> list){ if( list.value() == null ) return ; ListNode head = list.value(); ListNode rest = head.next ; if(rest==null) // a singular list return ; _<ListNode> reversed = new _<ListNode>(rest); reverseRecursive( reversed ); head.next.next = head ; head.next = null ; list.set(reversed.value()); }
public static void createEvenLengthList(_<ListNode> head, _<ListNode> front, _<ListNode> tail){ ListNode list = new ListNode(6); list.next = new ListNode(5); list.next.next = new ListNode(4); list.next.next.next = new ListNode(3); head.set(list); ListNode frontList = new ListNode(6); frontList.next = new ListNode(5); front.set(frontList); ListNode tailList = new ListNode(4); tailList.next = new ListNode(3); tail.set(tailList); }