剑指offer

输入一个链表，按链表值从尾到头的顺序返回一个ArrayList。

• 利用栈

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  class { public: vector<int> printListFromTailToHead(ListNode* head) { stack<ListNode*> nodes; vector<int> arrayList; ListNode* node = head; while(node != NULL) { nodes.push(node); node = node->next; } while(!nodes.empty()) { node = nodes.top(); arrayList.push_back(node->val); nodes.pop(); } return arrayList; } };

• 递归

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  class { public: vector<int> arrayList; vector<int> printListFromTailToHead(ListNode* head) { ListNode* node = head; if (node != NULL) { if (node->next != NULL) { printListFromTailToHead(node->next); } arrayList.push_back(node->val); } return arrayList; } };