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feat: update solutions to lc problem: No.0581
No.0581.Shortest Unsorted Continuous Subarray
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‎solution/0500-0599/0581.Shortest Unsorted Continuous Subarray/README.md

+53-17
Original file line numberDiff line numberDiff line change
@@ -55,7 +55,13 @@
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<!-- 这里可写通用的实现逻辑 -->
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58-
将排序后的数组与原数组进行比较，确定左右边界。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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时间复杂度 $O(nlogn)$，其中 $n$ 表示 $nums$ 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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<!-- tabs:start -->
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@@ -66,14 +72,13 @@
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```python
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class Solution:
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def findUnsortedSubarray(self, nums: List[int]) -> int:
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n = len(nums)
70-
numsSorted = sorted(nums)
71-
left, right = 0, n - 1
72-
while left < n and nums[left] == numsSorted[left]:
75+
arr = sorted(nums)
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left, right = 0, len(nums) - 1
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while left <= right and nums[left] == arr[left]:
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left += 1
74-
while right >= 0 and nums[right] == numsSorted[right]:
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while left <= right and nums[right] == arr[right]:
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right -= 1
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return 0 if right == -1 else right - left + 1
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return right - left + 1
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```
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### **Java**
@@ -83,24 +88,55 @@ class Solution:
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```java
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class Solution {
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public int findUnsortedSubarray(int[] nums) {
86-
int n = nums.length;
87-
int[] numsSorted = new int[n];
88-
System.arraycopy(nums, 0, numsSorted, 0, n);
89-
Arrays.sort(numsSorted);
90-
int left = 0, right = n - 1;
91-
while (left < n && nums[left] == numsSorted[left]) {
92-
left++;
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int[] arr = nums.clone();
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Arrays.sort(arr);
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int left = 0, right = nums.length - 1;
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while (left <= right && nums[left] == arr[left]) {
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++left;
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}
94-
while (right >= 0 && nums[right] == numsSorted[right]) {
95-
right--;
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while (left <= right && nums[right] == arr[right]) {
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--right;
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}
97-
return right == -1 ? 0 : right - left + 1;
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return right - left + 1;
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}
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}
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```
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### **C++**
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```cpp
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class Solution {
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public:
110+
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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}
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};
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```
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### **Go**
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```go
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func findUnsortedSubarray(nums []int) int {
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n := len(nums)
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arr := make([]int, n)
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copy(arr, nums)
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sort.Ints(arr)
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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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}
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for left <= right && nums[right] == arr[right] {
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right--
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}
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return right - left + 1
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}
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```
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```go
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func findUnsortedSubarray(nums []int) int {
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n := len(nums)

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

+46-16
Original file line numberDiff line numberDiff line change
@@ -51,39 +51,69 @@
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```python
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class Solution:
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def findUnsortedSubarray(self, nums: List[int]) -> int:
54-
n = len(nums)
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numsSorted = sorted(nums)
56-
left, right = 0, n - 1
57-
while left < n and nums[left] == numsSorted[left]:
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arr = sorted(nums)
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left, right = 0, len(nums) - 1
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while left <= right and nums[left] == arr[left]:
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left += 1
59-
while right >= 0 and nums[right] == numsSorted[right]:
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while left <= right and nums[right] == arr[right]:
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right -= 1
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return 0 if right == -1 else right - left + 1
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return right - left + 1
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```
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### **Java**
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```java
6766
class Solution {
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public int findUnsortedSubarray(int[] nums) {
69-
int n = nums.length;
70-
int[] numsSorted = new int[n];
71-
System.arraycopy(nums, 0, numsSorted, 0, n);
72-
Arrays.sort(numsSorted);
73-
int left = 0, right = n - 1;
74-
while (left < n && nums[left] == numsSorted[left]) {
75-
left++;
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int[] arr = nums.clone();
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Arrays.sort(arr);
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int left = 0, right = nums.length - 1;
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while (left <= right && nums[left] == arr[left]) {
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++left;
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}
77-
while (right >= 0 && nums[right] == numsSorted[right]) {
78-
right--;
74+
while (left <= right && nums[right] == arr[right]) {
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--right;
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}
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return right == -1 ? 0 : right - left + 1;
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return right - left + 1;
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}
8279
}
8380
```
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### **C++**
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```cpp
85+
class Solution {
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public:
87+
int findUnsortedSubarray(vector<int>& nums) {
88+
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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}
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};
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```
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### **Go**
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```go
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func findUnsortedSubarray(nums []int) int {
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n := len(nums)
103+
arr := make([]int, n)
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copy(arr, nums)
105+
sort.Ints(arr)
106+
left, right := 0, n-1
107+
for left <= right && nums[left] == arr[left] {
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left++
109+
}
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for left <= right && nums[right] == arr[right] {
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right--
112+
}
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return right - left + 1
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}
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```
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87117
```go
88118
func findUnsortedSubarray(nums []int) int {
89119
n := len(nums)

‎solution/0500-0599/0581.Shortest Unsorted Continuous Subarray/Solution.cpp

+7-36
Original file line numberDiff line numberDiff line change
@@ -1,40 +1,11 @@
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// i自左向右找到第一个逆序，
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// j自右向左找到第一个逆序
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// 找到nums[i, j]的上下界
4-
// ij向外扩展找到满足上下界的最小[i, j]
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class Solution {
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class Solution {
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public:
73
int findUnsortedSubarray(vector<int>& nums) {
8-
if (1 == nums.size())
9-
return 0 ;
10-
11-
int i = 0, j = nums.size()-1 ;
12-
while (i < j && nums[i] <= nums[i+1])
13-
++i ;
14-
if (i >= j)
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return 0 ;
16-
17-
while (nums[j-1] <= nums[j])
18-
--j ;
19-
20-
//cout << i << ' ' << j << endl ;
21-
int m = nums[i] ;
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int M = m ;
23-
for (int k = i; k <= j; ++k)
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{
25-
if (m > nums[k])
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m = nums[k] ;
27-
if (M < nums[k])
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M = nums[k] ;
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}
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//cout << m << ' ' << M << endl ;
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while (i >= 0 && m < nums[i])
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--i ;
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while (j < nums.size() && M > nums[j])
35-
++j ;
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//cout << i << ' ' << j << endl ;
38-
return j-i-1 ;
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vector<int> arr = nums;
5+
sort(arr.begin(), arr.end());
6+
int left = 0, right = arr.size() - 1;
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while (left <= right && nums[left] == arr[left]) ++left;
8+
while (left <= right && nums[right] == arr[right]) --right;
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return right - left + 1;
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}
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};

‎solution/0500-0599/0581.Shortest Unsorted Continuous Subarray/Solution.java

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@@ -1,16 +1,14 @@
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class Solution {
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public int findUnsortedSubarray(int[] nums) {
3-
int n = nums.length;
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int[] numsSorted = new int[n];
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System.arraycopy(nums, 0, numsSorted, 0, n);
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Arrays.sort(numsSorted);
7-
int left = 0, right = n - 1;
8-
while (left < n && nums[left] == numsSorted[left]) {
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left++;
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int[] arr = nums.clone();
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Arrays.sort(arr);
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int left = 0, right = nums.length - 1;
6+
while (left <= right && nums[left] == arr[left]) {
7+
++left;
108
}
11-
while (right >= 0 && nums[right] == numsSorted[right]) {
12-
right--;
9+
while (left <= right && nums[right] == arr[right]) {
10+
--right;
1311
}
14-
return right == -1 ? 0 : right - left + 1;
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return right - left + 1;
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}
16-
}
14+
}

‎solution/0500-0599/0581.Shortest Unsorted Continuous Subarray/Solution.py

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Original file line numberDiff line numberDiff line change
@@ -1,10 +1,9 @@
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class Solution:
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def findUnsortedSubarray(self, nums: List[int]) -> int:
3-
n = len(nums)
4-
numsSorted = sorted(nums)
5-
left, right = 0, n - 1
6-
while left < n and nums[left] == numsSorted[left]:
3+
arr = sorted(nums)
4+
left, right = 0, len(nums) - 1
5+
while left <= right and nums[left] == arr[left]:
76
left += 1
8-
while right >= 0 and nums[right] == numsSorted[right]:
7+
while left <= right and nums[right] == arr[right]:
98
right -= 1
10-
return 0 if right == -1 else right - left + 1
9+
return right - left + 1

‎solution/1000-1099/1037.Valid Boomerang/README.md

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**方法一：斜率比较**
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设三点分别为 $(x_1,y_1)$, $(x_2,y_2)$, $(x_3,y_3)$。
45+
设三点分别为 $(x_1,y_1)$, $(x_2,y_2)$, $(x_3,y_3)$。两点之间斜率计算公式为 $\frac{y_2-y_1}{x_2-x_1}$。
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47-
要使得三点不共线，需要满足 $\frac{y_2-y_1}{x_2-x_1}\neq\frac{y_3-y_2}{x_3-x_2}$，变形得 $(y_2-y_1)*(x_3-x_2) \neq (y_3-y_2)*(x_2-x_1)$。
47+
要使得三点不共线，需要满足 $\frac{y_2-y_1}{x_2-x_1}\neq\frac{y_3-y_2}{x_3-x_2}$，我们将式子变形得到 $(y_2-y_1)*(x_3-x_2) \neq (y_3-y_2)*(x_2-x_1)$。
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49+
注意：
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51+
1. 当两点之间斜率不存在，即 $x_1=x_2$，上述变式仍然成立；
52+
2. 若斜率除法运算比较存在精度问题，同样可以变换为乘法。
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54+
时间复杂度 $O(1)$。
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<!-- tabs:start -->
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