Add solution and test-cases for problem 2370

Author: 0xff-dev

leetcode/2301-2400/2370.Longest-Ideal-Subsequence/README.md

@@ -1,28 +1,33 @@
 # [2370.Longest Ideal Subsequence][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 a string `s` consisting of lowercase letters and an integer `k`. We call a string `t` **ideal** if the following conditions are satisfied:
+
+- `t` is a **subsequence** of the string `s`.
+- The absolute difference in the alphabet order of every two **adjacent** letters in `t` is less than or equal to `k`.
+
+Return the length of the **longest** ideal string.
+
+A **subsequence** is a string that can be derived from another string by deleting some or no characters without changing the order of the remaining characters.
+
+**Note** that the alphabet order is not cyclic. For example, the absolute difference in the alphabet order of `'a'` and `'z'` is `25`, not `1`.
 
 **Example 1:**
 
 ```
-Input: a = "11", b = "1"
-Output: "100"
+Input: s = "acfgbd", k = 2
+Output: 4
+Explanation: The longest ideal string is "acbd". The length of this string is 4, so 4 is returned.
+Note that "acfgbd" is not ideal because 'c' and 'f' have a difference of 3 in alphabet order.
 ```
 
-## 题意
-> ...
-
-## 题解
+**Example 2:**
 
-### 思路1
-> ...
-Longest Ideal Subsequence
-```go
 ```
-
+Input: s = "abcd", k = 3
+Output: 4
+Explanation: The longest ideal string is "abcd". The length of this string is 4, so 4 is returned.
+```
 
 ## 结语
 

leetcode/2301-2400/2370.Longest-Ideal-Subsequence/Solution.go

@@ -1,5 +1,35 @@
 package Solution
 
-func Solution(x bool) bool {
-	return x
+func Solution(s string, k int) int {
+	dis := [26]int{}
+	dis[s[0]-'a'] = 1
+	for i := 1; i < len(s); i++ {
+		td := uint8(0)
+		for ; td <= uint8(k); td++ {
+			if next := s[i] + td; next >= 'a' && next <= 'z' {
+				if dis[next-'a'] != 0 && dis[next-'a']+1 > dis[s[i]-'a'] {
+					dis[s[i]-'a'] = dis[next-'a'] + 1
+				}
+			}
+
+		}
+		td = uint8(1)
+		for ; td <= uint8(k); td++ {
+			if pre := s[i] - td; pre >= 'a' && pre <= 'z' {
+				if dis[pre-'a'] != 0 && dis[pre-'a']+1 > dis[s[i]-'a'] {
+					dis[s[i]-'a'] = dis[pre-'a'] + 1
+				}
+			}
+		}
+		if dis[s[i]-'a'] == 0 {
+			dis[s[i]-'a'] = 1
+		}
+	}
+	ans := 1
+	for i := 0; i < 26; i++ {
+		if dis[i] > ans {
+			ans = dis[i]
+		}
+	}
+	return ans
 }

leetcode/2301-2400/2370.Longest-Ideal-Subsequence/Solution_test.go

@@ -10,30 +10,31 @@ func TestSolution(t *testing.T) {
 	//	测试用例
 	cases := []struct {
 		name   string
-		inputs bool
-		expect bool
+		inputs string
+		k      int
+		expect int
 	}{
-		{"TestCase", true, true},
-		{"TestCase", true, true},
-		{"TestCase", false, false},
+		{"TestCase1", "acfgbd", 2, 4},
+		{"TestCase2", "abcd", 3, 4},
+		{"TestCase3", "pvjcci", 4, 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.inputs, 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.inputs, 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() {
 }