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Commit 3007c80

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feat: add solutions to lc problems: No.0577,0580,0581,1661 (doocs#1830)
* No.0577.Employee Bonus * No.0580.Count Student Number in Departments * No.0581.Shortest Unsorted Continuous Subarray * No.1661.Average Time of Process per Machine
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‎.prettierrc‎

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"solution/1500-1599/1501.Countries You Can Safely Invest In/Solution.sql",
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"solution/1500-1599/1511.Customer Order Frequency/Solution.sql",
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"solution/1500-1599/1555.Bank Account Summary/Solution.sql",
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"solution/1600-1699/1661.Average Time of Process per Machine/Solution.sql",
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"solution/1600-1699/1667.Fix Names in a Table/Solution.sql",
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"solution/1600-1699/1699.Number of Calls Between Two Persons/Solution.sql",
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"solution/1700-1799/1777.Product's Price for Each Store/Solution.sql",

‎solution/0500-0599/0577.Employee Bonus/README.md‎

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<!-- 这里可写通用的实现逻辑 -->
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**方法一:左连接**
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我们可以使用左连接,将 `Employee` 表和 `Bonus` 表按照 `empId` 进行连接,然后筛选出奖金小于 1000ドル$ 的员工。注意,连接后的表中,`bonus` 为 `NULL` 的员工也应该被筛选出来,因此我们需要使用 `IFNULL` 函数将 `NULL` 值转换为 0ドル$。
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<!-- tabs:start -->
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### **SQL**

‎solution/0500-0599/0577.Employee Bonus/README_EN.md‎

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## Solutions
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**Solution 1: Left Join**
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We can use a left join to join the `Employee` table and the `Bonus` table on `empId`, and then filter out the employees whose bonus is less than 1000ドル$. Note that the employees with `NULL` bonus values after the join should also be filtered out, so we need to use the `IFNULL` function to convert `NULL` values to 0ドル$.
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<!-- tabs:start -->
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### **SQL**

‎solution/0500-0599/0580.Count Student Number in Departments/README.md‎

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@@ -79,22 +79,21 @@ Department 表:
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<!-- 这里可写通用的实现逻辑 -->
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**方法一:左连接 + 分组统计**
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我们可以使用左连接,将 `Department` 表与 `Student` 表按照 `dept_id` 进行连接,然后按照 `dept_id` 分组统计学生人数,最后按照 `student_number` 降序、`dept_name` 升序排序即可。
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<!-- tabs:start -->
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### **SQL**
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```sql
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# Write your MySQL query statement below
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WITH
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S AS (
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SELECT dept_id, COUNT(1) AS cnt
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FROM Student
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GROUP BY dept_id
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)
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SELECT dept_name, IFNULL(cnt, 0) AS student_number
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SELECT dept_name, COUNT(student_id) AS student_number
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FROM
96-
S
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RIGHT JOIN Department USING (dept_id)
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Department
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LEFT JOIN Student USING (dept_id)
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GROUP BY dept_id
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ORDER BY 2 DESC, 1;
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```
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‎solution/0500-0599/0580.Count Student Number in Departments/README_EN.md‎

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## Solutions
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**Solution 1: Left Join + Grouping**
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We can use a left join to join the `Department` table and the `Student` table on `dept_id`, and then group by `dept_id` to count the number of students in each department. Finally, we can sort the result by `student_number` in descending order and `dept_name` in ascending order.
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<!-- tabs:start -->
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### **SQL**
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```sql
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# Write your MySQL query statement below
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WITH
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S AS (
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SELECT dept_id, COUNT(1) AS cnt
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FROM Student
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GROUP BY dept_id
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)
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SELECT dept_name, IFNULL(cnt, 0) AS student_number
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SELECT dept_name, COUNT(student_id) AS student_number
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FROM
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S
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RIGHT JOIN Department USING (dept_id)
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Department
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LEFT JOIN Student USING (dept_id)
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GROUP BY dept_id
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ORDER BY 2 DESC, 1;
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```
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# Write your MySQL query statement below
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WITH
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S AS (
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SELECT dept_id, COUNT(1) AS cnt
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FROM Student
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GROUP BY dept_id
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)
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SELECT dept_name, IFNULL(cnt, 0) AS student_number
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SELECT dept_name, COUNT(student_id) AS student_number
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FROM
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S
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RIGHT JOIN Department USING (dept_id)
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Department
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LEFT JOIN Student USING (dept_id)
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GROUP BY dept_id
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ORDER BY 2 DESC, 1;

‎solution/0500-0599/0581.Shortest Unsorted Continuous Subarray/README.md‎

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**方法一:排序**
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将排序后的数组与原数组进行比较,确定左右边界。
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我们可以先对数组进行排序,然后比较排序后的数组和原数组,找到最左边和最右边不相等的位置,它们之间的长度就是我们要找的最短无序连续子数组的长度。
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时间复杂度 $O(nlogn),ドル其中 $n$ 表示 $nums$ 数组的长度。
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时间复杂度 $O(n \times \log n),ドル空间复杂度 $O(n)$。其中 $n$ 是数组的长度。
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更进一步优化,可以通过维护最大值和最小值,一次遍历得出结果(见 Golang 解法)
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**方法二:维护左侧最大值和右侧最小值**
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我们可以从左到右遍历数组,维护一个最大值 $mx,ドル如果当前值小于 $mx,ドル说明当前值不在正确的位置上,我们更新右边界 $r$ 为当前位置。同理,我们可以从右到左遍历数组,维护一个最小值 $mi,ドル如果当前值大于 $mi,ドル说明当前值不在正确的位置上,我们更新左边界 $l$ 为当前位置。在初始化时,我们将 $l$ 和 $r$ 都初始化为 $-1,ドル如果 $l$ 和 $r$ 都没有被更新,说明数组已经有序,返回 0ドル,ドル否则返回 $r - l + 1$。
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时间复杂度 $O(n),ドル其中 $n$ 是数组的长度。空间复杂度 $O(1)$。
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<!-- tabs:start -->
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class Solution:
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def findUnsortedSubarray(self, nums: List[int]) -> int:
7579
arr = sorted(nums)
76-
left, right = 0, len(nums) - 1
77-
while left <= right and nums[left] == arr[left]:
78-
left += 1
79-
while left <= right and nums[right] == arr[right]:
80-
right -= 1
81-
return right - left + 1
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l, r = 0, len(nums) - 1
81+
while l <= r and nums[l] == arr[l]:
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l += 1
83+
while l <= r and nums[r] == arr[r]:
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r -= 1
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return r - l + 1
86+
```
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```python
89+
class Solution:
90+
def findUnsortedSubarray(self, nums: List[int]) -> int:
91+
mi, mx = inf, -inf
92+
l = r = -1
93+
n = len(nums)
94+
for i, x in enumerate(nums):
95+
if mx > x:
96+
r = i
97+
else:
98+
mx = x
99+
if mi < nums[n - i - 1]:
100+
l = n - i - 1
101+
else:
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mi = nums[n - i - 1]
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return 0 if r == -1 else r - l + 1
82104
```
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84106
### **Java**
@@ -90,14 +112,38 @@ class Solution {
90112
public int findUnsortedSubarray(int[] nums) {
91113
int[] arr = nums.clone();
92114
Arrays.sort(arr);
93-
int left = 0, right = nums.length - 1;
94-
while (left <= right && nums[left] == arr[left]) {
95-
++left;
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int l = 0, r = arr.length - 1;
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while (l <= r && nums[l] == arr[l]) {
117+
l++;
96118
}
97-
while (left <= right && nums[right] == arr[right]) {
98-
--right;
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while (l <= r && nums[r] == arr[r]) {
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r--;
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}
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return right - left + 1;
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return r - l + 1;
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}
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}
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```
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```java
128+
class Solution {
129+
public int findUnsortedSubarray(int[] nums) {
130+
final int inf = 1 << 30;
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int n = nums.length;
132+
int l = -1, r = -1;
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int mi = inf, mx = -inf;
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for (int i = 0; i < n; ++i) {
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if (mx > nums[i]) {
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r = i;
137+
} else {
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mx = nums[i];
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}
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if (mi < nums[n - i - 1]) {
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l = n - i - 1;
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} else {
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mi = nums[n - i - 1];
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}
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}
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return r == -1 ? 0 : r - l + 1;
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}
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}
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```
@@ -110,10 +156,39 @@ public:
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int findUnsortedSubarray(vector<int>& nums) {
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vector<int> arr = nums;
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sort(arr.begin(), arr.end());
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int left = 0, right = arr.size() - 1;
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while (left <= right && nums[left] == arr[left]) ++left;
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while (left <= right && nums[right] == arr[right]) --right;
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return right - left + 1;
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int l = 0, r = arr.size() - 1;
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while (l <= r && arr[l] == nums[l]) {
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l++;
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}
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while (l <= r && arr[r] == nums[r]) {
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r--;
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}
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return r - l + 1;
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}
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};
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```
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```cpp
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class Solution {
173+
public:
174+
int findUnsortedSubarray(vector<int>& nums) {
175+
const int inf = 1e9;
176+
int n = nums.size();
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int l = -1, r = -1;
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int mi = inf, mx = -inf;
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for (int i = 0; i < n; ++i) {
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if (mx > nums[i]) {
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r = i;
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} else {
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mx = nums[i];
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}
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if (mi < nums[n - i - 1]) {
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l = n - i - 1;
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} else {
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mi = nums[n - i - 1];
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}
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}
191+
return r == -1 ? 0 : r - l + 1;
117192
}
118193
};
119194
```
@@ -122,42 +197,113 @@ public:
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```go
124199
func findUnsortedSubarray(nums []int) int {
125-
n := len(nums)
126-
arr := make([]int, n)
200+
arr := make([]int, len(nums))
127201
copy(arr, nums)
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sort.Ints(arr)
129-
left, right := 0, n-1
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for left <= right && nums[left] == arr[left] {
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left++
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l, r := 0, len(arr)-1
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for l <= r && nums[l] == arr[l] {
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l++
132206
}
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for left <= right && nums[right] == arr[right] {
134-
right--
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for l <= r && nums[r] == arr[r] {
208+
r--
135209
}
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return right - left + 1
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return r - l + 1
137211
}
138212
```
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```go
141215
func findUnsortedSubarray(nums []int) int {
216+
const inf = 1 << 30
142217
n := len(nums)
143-
maxn, minn := math.MinInt32, math.MaxInt32
144-
left, right := -1, -1
145-
for i:= 0; i < n; i++ {
146-
if maxn > nums[i] {
147-
right = i
218+
l, r := -1, -1
219+
mi, mx := inf, -inf
220+
for i, x:= range nums {
221+
if mx > x {
222+
r = i
148223
} else {
149-
maxn = nums[i]
224+
mx = x
150225
}
151-
if minn < nums[n-i-1] {
152-
left = n - i - 1
226+
if mi < nums[n-i-1] {
227+
l = n - i - 1
153228
} else {
154-
minn = nums[n-i-1]
229+
mi = nums[n-i-1]
155230
}
156231
}
157-
if right == -1 {
232+
if r == -1 {
158233
return 0
159234
}
160-
return right - left + 1
235+
return r - l + 1
236+
}
237+
```
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### **TypeScript**
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```ts
242+
function findUnsortedSubarray(nums: number[]): number {
243+
const arr = [...nums];
244+
arr.sort((a, b) => a - b);
245+
let [l, r] = [0, arr.length - 1];
246+
while (l <= r && arr[l] === nums[l]) {
247+
++l;
248+
}
249+
while (l <= r && arr[r] === nums[r]) {
250+
--r;
251+
}
252+
return r - l + 1;
253+
}
254+
```
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```ts
257+
function findUnsortedSubarray(nums: number[]): number {
258+
let [l, r] = [-1, -1];
259+
let [mi, mx] = [Infinity, -Infinity];
260+
const n = nums.length;
261+
for (let i = 0; i < n; ++i) {
262+
if (mx > nums[i]) {
263+
r = i;
264+
} else {
265+
mx = nums[i];
266+
}
267+
if (mi < nums[n - i - 1]) {
268+
l = n - i - 1;
269+
} else {
270+
mi = nums[n - i - 1];
271+
}
272+
}
273+
return r === -1 ? 0 : r - l + 1;
274+
}
275+
```
276+
277+
```rust
278+
impl Solution {
279+
pub fn find_unsorted_subarray(nums: Vec<i32>) -> i32 {
280+
let inf = 1 << 30;
281+
let n = nums.len();
282+
let mut l = -1;
283+
let mut r = -1;
284+
let mut mi = inf;
285+
let mut mx = -inf;
286+
287+
for i in 0..n {
288+
if mx > nums[i] {
289+
r = i as i32;
290+
} else {
291+
mx = nums[i];
292+
}
293+
294+
if mi < nums[n - i - 1] {
295+
l = (n - i - 1) as i32;
296+
} else {
297+
mi = nums[n - i - 1];
298+
}
299+
}
300+
301+
if r == -1 {
302+
0
303+
} else {
304+
r - l + 1
305+
}
306+
}
161307
}
162308
```
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