剑指 Offer 06. 从尾到头打印链表

Recursion

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class Solution {
public int[] reversePrint(ListNode head) {
List<Integer> list = new LinkedList<>();
recur(list, head);

int[] array = new int[list.size()];
for (int i = 0; i < list.size(); i++) {
array[i] = list.get(i);
}
return array;
}

private void recur(List<Integer> list, ListNode node) {
if (node == null) {
return;
}

recur(list, node.next);
list.add(node.val);
}
}

Linked List

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class Solution {
public int[] reversePrint(ListNode head) {
Deque<Integer> deque = new LinkedList<>();
ListNode node = head;
while (node != null) {
deque.addLast(node.val);
node = node.next;
}

int[] array = new int[deque.size()];
for (int i = 0; i < array.length; i++) {
array[i] = deque.removeLast();
}
return array;
}
}

References

剑指 Offer 06. 从尾到头打印链表