leetcode.ipynb

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    "### leetcode 链表反转\n",
    "定义一个函数，输入一个链表的头节点，反转该链表并输出反转后链表的头节点。\n",
    "\n",
    " \n",
    "\n",
    "#### 示例:\n",
    "\n",
    "输入: `1->2->3->4->5->NULL`\n",
    "输出: `5->4->3->2->1->NULL`\n",
    " \n",
    "\n",
    "#### 限制：\n",
    "\n",
    "0 <= 节点个数 <= 5000"
   ]
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   "source": [
    "%run node.py\n",
    "\n",
    "class Solution:\n",
    "    def reverseList(head: ListNode) -> ListNode:\n",
    "        last = None\n",
    "        while head:\n",
    "            head.next, last, head = last, head, head.next\n",
    "        return last\n",
    "\n",
    "print('reversed:',Solution.reverseList(list))"
   ]
  }
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