Merge pull request #1349 from 0xff-dev/3347

Add solution and test-cases for problem 3347

Author: 6boris

leetcode/3301-3400/3347.Maximum-Frequency-of-an-Element-After-Performing-Operations-II/README.md

@@ -1,28 +1,43 @@
 # [3347.Maximum Frequency of an Element After Performing Operations II][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 two integers `k` and `numOperations`.
+
+You must perform an **operation** numOperations times on `nums`, where in each operation you:
+
+- Select an index `i` that was **not** selected in any previous operations.
+- Add an integer in the range `[-k, k]` to `nums[i]`.
+
+Return the **maximum** possible frequency of any element in `nums` after performing the **operations**.
 
 **Example 1:**
 
 ```
-Input: a = "11", b = "1"
-Output: "100"
-```
+Input: nums = [1,4,5], k = 1, numOperations = 2
+
+Output: 2
 
-## 题意
-> ...
+Explanation:
 
-## 题解
+We can achieve a maximum frequency of two by:
 
-### 思路1
-> ...
-Maximum Frequency of an Element After Performing Operations II
-```go
+Adding 0 to nums[1], after which nums becomes [1, 4, 5].
+Adding -1 to nums[2], after which nums becomes [1, 4, 4].
 ```
 
+**Example 2:**
+
+```
+Input: nums = [5,11,20,20], k = 5, numOperations = 1
+
+Output: 2
+
+Explanation:
+
+We can achieve a maximum frequency of two by:
+
+Adding 0 to nums[1].
+```
 
 ## 结语
 

leetcode/3301-3400/3347.Maximum-Frequency-of-an-Element-After-Performing-Operations-II/Solution.go

@@ -1,5 +1,86 @@
 package Solution
 
-func Solution(x bool) bool {
-	return x
+import "sort"
+
+func Solution(nums []int, k int, numOperations int) int {
+	sort.Ints(nums)
+	ans := 0
+	numCount := make(map[int]int)
+	modes := make(map[int]bool)
+
+	addMode := func(value int) {
+		modes[value] = true
+		if value-k >= nums[0] {
+			modes[value-k] = true
+		}
+		if value+k <= nums[len(nums)-1] {
+			modes[value+k] = true
+		}
+	}
+
+	lastNumIndex := 0
+	for i := 0; i < len(nums); i++ {
+		if nums[i] != nums[lastNumIndex] {
+			numCount[nums[lastNumIndex]] = i - lastNumIndex
+			if i-lastNumIndex > ans {
+				ans = i - lastNumIndex
+			}
+			addMode(nums[lastNumIndex])
+			lastNumIndex = i
+		}
+	}
+
+	numCount[nums[lastNumIndex]] = len(nums) - lastNumIndex
+	if len(nums)-lastNumIndex > ans {
+		ans = len(nums) - lastNumIndex
+	}
+	addMode(nums[lastNumIndex])
+
+	leftBound := func(value int) int {
+		left, right := 0, len(nums)-1
+		for left < right {
+			mid := (left + right) / 2
+			if nums[mid] < value {
+				left = mid + 1
+			} else {
+				right = mid
+			}
+		}
+		return left
+	}
+
+	rightBound := func(value int) int {
+		left, right := 0, len(nums)-1
+		for left < right {
+			mid := (left + right + 1) / 2
+			if nums[mid] > value {
+				right = mid - 1
+			} else {
+				left = mid
+			}
+		}
+		return left
+	}
+
+	uniqueModes := make([]int, 0, len(modes))
+	for mode := range modes {
+		uniqueModes = append(uniqueModes, mode)
+	}
+	sort.Ints(uniqueModes)
+
+	for _, mode := range uniqueModes {
+		l := leftBound(mode - k)
+		r := rightBound(mode + k)
+		var tempAns int
+		if count, exists := numCount[mode]; exists {
+			tempAns = min(r-l+1, count+numOperations)
+		} else {
+			tempAns = min(r-l+1, numOperations)
+		}
+		if tempAns > ans {
+			ans = tempAns
+		}
+	}
+
+	return ans
 }

leetcode/3301-3400/3347.Maximum-Frequency-of-an-Element-After-Performing-Operations-II/Solution_test.go

@@ -9,31 +9,32 @@ import (
 func TestSolution(t *testing.T) {
 	//	测试用例
 	cases := []struct {
-		name   string
-		inputs bool
-		expect bool
+		name          string
+		nums          []int
+		k             int
+		numOperations int
+		expect        int
 	}{
-		{"TestCase", true, true},
-		{"TestCase", true, true},
-		{"TestCase", false, false},
+		{"TestCase1", []int{1, 4, 5}, 1, 2, 2},
+		{"TestCase2", []int{5, 11, 20, 20}, 5, 1, 2},
 	}
 
 	//	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, c.numOperations)
 			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 %v",
+					c.expect, got, c.nums, c.k, c.numOperations)
 			}
 		})
 	}
 }
 
-//	压力测试
+// 压力测试
 func BenchmarkSolution(b *testing.B) {
 }
 
-//	使用案列
+// 使用案列
 func ExampleSolution() {
 }