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‎Problemset/1095-Find in Mountain Array/README.md

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# 1095. Find in Mountain Array
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*(This problem is an **interactive problem**.)*
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You may recall that an array `arr` is a **mountain array** if and only if:
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* `arr.length >= 3`
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* There exists some `i` with `0 < i < arr.length - 1` such that:
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* `arr[0] < arr[1] < ... < arr[i - 1] < arr[i]`
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* `arr[i] > arr[i + 1] > ... > arr[arr.length - 1]`
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Given a mountain array `mountainArr`, return the **minimum** `index` such that `mountainArr.get(index) == target`. If such an `index` does not exist, return `-1`.
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**You cannot access the mountain array directly**. You may only access the array using a `MountainArray` interface:
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* `MountainArray.get(k)` returns the element of the array at index `k` (0-indexed).
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* `MountainArray.length()` returns the length of the array.
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Submissions making more than `100` calls to `MountainArray.get` will be judged *Wrong Answer*. Also, any solutions that attempt to circumvent the judge will result in disqualification.
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#### Example 1:
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<pre>
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<strong>Input:</strong> mountainArr = [1,2,3,4,5,3,1], target = 3
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<strong>Output:</strong> 2
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<strong>Explanation:</strong> 3 exists in the array, at index=2 and index=5. Return the minimum index, which is 2.
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</pre>
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#### Example 2:
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<pre>
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<strong>Input:</strong> mountainArr = [0,1,2,4,2,1], target = 3
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<strong>Output:</strong> -1
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<strong>Explanation:</strong> 3 does not exist in the array, so we return -1.
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</pre>
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#### Constraints:
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* <code>3 <= mountainArr.length() <= 10<sup>4</sup></code>
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* <code>0 <= target <= 10<sup>9</sup></code>
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* <code>0 <= mountainArr.get(index) <= 10<sup>9</sup></code>
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## Solutions (Python)
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### 1. Solution
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```Python
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# """
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# This is MountainArray's API interface.
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# You should not implement it, or speculate about its implementation
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# """
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# class MountainArray:
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# def get(self, index: int) -> int:
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# def length(self) -> int:
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class Solution:
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def findInMountainArray(self, target: int, mountainArr: 'MountainArray') -> int:
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n = mountainArr.length()
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i = bisect.bisect(range(n - 1), False, key=lambda j: mountainArr.get(
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j) > mountainArr.get(j + 1))
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index = bisect.bisect_left(range(n), target, hi=i, key=mountainArr.get)
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if mountainArr.get(index) == target:
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return index
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index = bisect.bisect_left(
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range(n - 1), -target, lo=i, key=lambda j: -mountainArr.get(j))
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if mountainArr.get(index) == target:
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return index
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return -1
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```

‎Problemset/1095-Find in Mountain Array/README_CN.md

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# 1095. 山脉数组中查找目标值
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（这是一个 **交互式问题** ）
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你可以将一个数组 `arr` 称为 **山脉数组** 当且仅当：
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* `arr.length >= 3`
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* 存在一些 `0 < i < arr.length - 1` 的 `i` 使得：
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* `arr[0] < arr[1] < ... < arr[i - 1] < arr[i]`
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* `arr[i] > arr[i + 1] > ... > arr[arr.length - 1]`
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给定一个山脉数组 `mountainArr` ，返回 **最小** 的 `index` 使得 `mountainArr.get(index) == target`。如果不存在这样的 `index`，返回 `-1` 。
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**你无法直接访问山脉数组**。你只能使用 `MountainArray` 接口来访问数组：
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* `MountainArray.get(k)` 返回数组中下标为 `k` 的元素（从 0 开始）。
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* `MountainArray.length()` 返回数组的长度。
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调用 `MountainArray.get` 超过 `100` 次的提交会被判定为错误答案。此外，任何试图绕过在线评测的解决方案都将导致取消资格。
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#### 示例 1:
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<pre>
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<strong>输入:</strong> mountainArr = [1,2,3,4,5,3,1], target = 3
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<strong>输出:</strong> 2
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<strong>解释:</strong> 3 在数组中出现了两次，下标分别为 2 和 5，我们返回最小的下标 2。
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</pre>
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#### 示例 2:
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<pre>
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<strong>输入:</strong> mountainArr = [0,1,2,4,2,1], target = 3
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<strong>输出:</strong> -1
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<strong>解释:</strong> 3 在数组中没有出现，返回 -1。
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</pre>
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#### 提示:
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* <code>3 <= mountainArr.length() <= 10<sup>4</sup></code>
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* <code>0 <= target <= 10<sup>9</sup></code>
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* <code>0 <= mountainArr.get(index) <= 10<sup>9</sup></code>
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## 题解 (Python)
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### 1. 题解
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```Python
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# """
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# This is MountainArray's API interface.
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# You should not implement it, or speculate about its implementation
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# """
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# class MountainArray:
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# def get(self, index: int) -> int:
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# def length(self) -> int:
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class Solution:
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def findInMountainArray(self, target: int, mountainArr: 'MountainArray') -> int:
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n = mountainArr.length()
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i = bisect.bisect(range(n - 1), False, key=lambda j: mountainArr.get(
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j) > mountainArr.get(j + 1))
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index = bisect.bisect_left(range(n), target, hi=i, key=mountainArr.get)
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if mountainArr.get(index) == target:
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return index
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index = bisect.bisect_left(
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range(n - 1), -target, lo=i, key=lambda j: -mountainArr.get(j))
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if mountainArr.get(index) == target:
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return index
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return -1
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```

‎Problemset/1095-Find in Mountain Array/Solution.py

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# """
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# This is MountainArray's API interface.
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# You should not implement it, or speculate about its implementation
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# """
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# class MountainArray:
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# def get(self, index: int) -> int:
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# def length(self) -> int:
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class Solution:
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def findInMountainArray(self, target: int, mountainArr: 'MountainArray') -> int:
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n = mountainArr.length()
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i = bisect.bisect(range(n - 1), False, key=lambda j: mountainArr.get(
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j) > mountainArr.get(j + 1))
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index = bisect.bisect_left(range(n), target, hi=i, key=mountainArr.get)
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if mountainArr.get(index) == target:
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return index
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index = bisect.bisect_left(
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range(n - 1), -target, lo=i, key=lambda j: -mountainArr.get(j))
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if mountainArr.get(index) == target:
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return index
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return -1

‎README.md

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[1091][1091l]|[Shortest Path in Binary Matrix][1091] |![rs]
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[1093][1093l]|[Statistics from a Large Sample][1093] |![rs]
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[1094][1094l]|[Car Pooling][1094] |![rs]
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[1095][1095l]|[Find in Mountain Array][1095] |![py]
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[1103][1103l]|[Distribute Candies to People][1103] |![py]
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[1104][1104l]|[Path In Zigzag Labelled Binary Tree][1104] |![rs]
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[1105][1105l]|[Filling Bookcase Shelves][1105] |![rs]
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[1091]:Problemset/1091-Shortest%20Path%20in%20Binary%20Matrix/README.md#1091-shortest-path-in-binary-matrix
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[1093]:Problemset/1093-Statistics%20from%20a%20Large%20Sample/README.md#1093-statistics-from-a-large-sample
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[1094]:Problemset/1094-Car%20Pooling/README.md#1094-car-pooling
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[1095]:Problemset/1095-Find%20in%20Mountain%20Array/README.md#1095-find-in-mountain-array
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[1103]:Problemset/1103-Distribute%20Candies%20to%20People/README.md#1103-distribute-candies-to-people
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[1104]:Problemset/1104-Path%20In%20Zigzag%20Labelled%20Binary%20Tree/README.md#1104-path-in-zigzag-labelled-binary-tree
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[1105]:Problemset/1105-Filling%20Bookcase%20Shelves/README.md#1105-filling-bookcase-shelves
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[1091l]:https://leetcode.com/problems/shortest-path-in-binary-matrix/
41284130
[1093l]:https://leetcode.com/problems/statistics-from-a-large-sample/
41294131
[1094l]:https://leetcode.com/problems/car-pooling/
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[1095l]:https://leetcode.com/problems/find-in-mountain-array/
41304133
[1103l]:https://leetcode.com/problems/distribute-candies-to-people/
41314134
[1104l]:https://leetcode.com/problems/path-in-zigzag-labelled-binary-tree/
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[1105l]:https://leetcode.com/problems/filling-bookcase-shelves/

‎README_CN.md

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[1091][1091l]|[二进制矩阵中的最短路径][1091] |![rs]
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[1093][1093l]|[大样本统计][1093] |![rs]
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[1094][1094l]|[拼车][1094] |![rs]
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[1095][1095l]|[山脉数组中查找目标值][1095] |![py]
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[1103][1103l]|[分糖果 II][1103] |![py]
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[1104][1104l]|[二叉树寻路][1104] |![rs]
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[1105][1105l]|[填充书架][1105] |![rs]
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[1091]:Problemset/1091-Shortest%20Path%20in%20Binary%20Matrix/README_CN.md#1091-二进制矩阵中的最短路径
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[1093]:Problemset/1093-Statistics%20from%20a%20Large%20Sample/README_CN.md#1093-大样本统计
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[1094]:Problemset/1094-Car%20Pooling/README_CN.md#1094-拼车
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[1095]:Problemset/1095-Find%20in%20Mountain%20Array/README_CN.md#1095-山脉数组中查找目标值
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[1103]:Problemset/1103-Distribute%20Candies%20to%20People/README_CN.md#1103-分糖果-ii
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[1104]:Problemset/1104-Path%20In%20Zigzag%20Labelled%20Binary%20Tree/README_CN.md#1104-二叉树寻路
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[1105]:Problemset/1105-Filling%20Bookcase%20Shelves/README_CN.md#1105-填充书架
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[1091l]:https://leetcode.cn/problems/shortest-path-in-binary-matrix/
41284130
[1093l]:https://leetcode.cn/problems/statistics-from-a-large-sample/
41294131
[1094l]:https://leetcode.cn/problems/car-pooling/
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[1095l]:https://leetcode.cn/problems/find-in-mountain-array/
41304133
[1103l]:https://leetcode.cn/problems/distribute-candies-to-people/
41314134
[1104l]:https://leetcode.cn/problems/path-in-zigzag-labelled-binary-tree/
41324135
[1105l]:https://leetcode.cn/problems/filling-bookcase-shelves/

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