33 lines
921 B
Java
33 lines
921 B
Java
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# 32.2 把二叉树打印成多行
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[NowCoder](https://www.nowcoder.com/practice/445c44d982d04483b04a54f298796288?tpId=13&tqId=11213&tPage=1&rp=1&ru=/ta/coding-interviews&qru=/ta/coding-interviews/question-ranking&from=cyc_github)
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## 题目描述
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和上题几乎一样。
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## 解题思路
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```java
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ArrayList<ArrayList<Integer>> Print(TreeNode pRoot) {
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ArrayList<ArrayList<Integer>> ret = new ArrayList<>();
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Queue<TreeNode> queue = new LinkedList<>();
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queue.add(pRoot);
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while (!queue.isEmpty()) {
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ArrayList<Integer> list = new ArrayList<>();
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int cnt = queue.size();
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while (cnt-- > 0) {
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TreeNode node = queue.poll();
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if (node == null)
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continue;
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list.add(node.val);
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queue.add(node.left);
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queue.add(node.right);
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}
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if (list.size() != 0)
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ret.add(list);
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}
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return ret;
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}
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```
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