剑指offer:从尾到头打印链表(java)

/**
* 从尾到头打印链表
* @param root
*/
public static void printReverseList(ListNode root){
if(root==null) return;
ListNode node = root;
Stack<ListNode> stack = new Stack<ListNode>();
while(node!=null){
stack.push(node);
node = node.next;
}
while(!stack.isEmpty()){
int val = stack.pop().val;
System.out.print(val+" ");
}
}

/**
* 递归写法
* @param root
*/
public static void printReverseListRecursive(ListNode root){
if(root==null) return;
if(root.next!=null)
printReverseList(root.next);
System.out.print(root.val+" ");
}