Merge pull request #1037 from 0xff-dev/2461

Add solution and test-cases for problem 2461

Author: 6boris

leetcode/2401-2500/2461.Maximum-Sum-of-Distinct-Subarrays-With-Length-K/README.md

@@ -1,28 +1,38 @@
 # [2461.Maximum Sum of Distinct Subarrays With Length K][title]
 
-> [!WARNING|style:flat]
-> This question is temporarily unanswered if you have good ideas. Welcome to [Create Pull Request PR](https://github.com/kylesliu/awesome-golang-algorithm)
-
 ## Description
+You are given an integer array `nums` and an integer `k`. Find the maximum subarray sum of all the subarrays of `nums` that meet the following conditions:
+
+- The length of the subarray is `k`, and
+- All the elements of the subarray are **distinct**.
+
+Return the maximum subarray sum of all the subarrays that meet the conditions. If no subarray meets the conditions, return `0`.
+
+A **subarray** is a contiguous non-empty sequence of elements within an array.
 
 **Example 1:**
 
 ```
-Input: a = "11", b = "1"
-Output: "100"
+Input: nums = [1,5,4,2,9,9,9], k = 3
+Output: 15
+Explanation: The subarrays of nums with length 3 are:
+- [1,5,4] which meets the requirements and has a sum of 10.
+- [5,4,2] which meets the requirements and has a sum of 11.
+- [4,2,9] which meets the requirements and has a sum of 15.
+- [2,9,9] which does not meet the requirements because the element 9 is repeated.
+- [9,9,9] which does not meet the requirements because the element 9 is repeated.
+We return 15 because it is the maximum subarray sum of all the subarrays that meet the conditions
 ```
 
-## 题意
-> ...
+**Example 2:**
 
-## 题解
-
-### 思路1
-> ...
-Maximum Sum of Distinct Subarrays With Length K
-```go
 ```
-
+Input: nums = [4,4,4], k = 3
+Output: 0
+Explanation: The subarrays of nums with length 3 are:
+- [4,4,4] which does not meet the requirements because the element 4 is repeated.
+We return 0 because no subarrays meet the conditions.
+```
 
 ## 结语
 

leetcode/2401-2500/2461.Maximum-Sum-of-Distinct-Subarrays-With-Length-K/Solution.go

@@ -1,5 +1,32 @@
 package Solution
 
-func Solution(x bool) bool {
-	return x
+func Solution(nums []int, k int) int64 {
+	l := len(nums)
+	count := make(map[int]int)
+	cur := int64(0)
+	for i := 0; i < k; i++ {
+		count[nums[i]]++
+		cur += int64(nums[i])
+	}
+
+	ans := int64(0)
+	if len(count) == k {
+		ans = cur
+	}
+
+	// [1, 2], 3, 4,
+	s, e := 0, k
+	for ; e < l; s, e = s+1, e+1 {
+		count[nums[s]]--
+		cur -= int64(nums[s])
+		if count[nums[s]] == 0 {
+			delete(count, nums[s])
+		}
+		count[nums[e]]++
+		cur += int64(nums[e])
+		if len(count) == k {
+			ans = max(ans, cur)
+		}
+	}
+	return ans
 }

leetcode/2401-2500/2461.Maximum-Sum-of-Distinct-Subarrays-With-Length-K/Solution_test.go

@@ -10,30 +10,30 @@ func TestSolution(t *testing.T) {
 	//	测试用例
 	cases := []struct {
 		name   string
-		inputs bool
-		expect bool
+		nums   []int
+		k      int
+		expect int64
 	}{
-		{"TestCase", true, true},
-		{"TestCase", true, true},
-		{"TestCase", false, false},
+		{"TestCase1", []int{1, 5, 4, 2, 9, 9, 9}, 3, 15},
+		{"TestCase2", []int{4, 4, 4}, 3, 0},
 	}
 
 	//	开始测试
 	for i, c := range cases {
 		t.Run(c.name+" "+strconv.Itoa(i), func(t *testing.T) {
-			got := Solution(c.inputs)
+			got := Solution(c.nums, c.k)
 			if !reflect.DeepEqual(got, c.expect) {
-				t.Fatalf("expected: %v, but got: %v, with inputs: %v",
-					c.expect, got, c.inputs)
+				t.Fatalf("expected: %v, but got: %v, with inputs: %v %v",
+					c.expect, got, c.nums, c.k)
 			}
 		})
 	}
 }
 
-//	压力测试
+// 压力测试
 func BenchmarkSolution(b *testing.B) {
 }
 
-//	使用案列
+// 使用案列
 func ExampleSolution() {
 }