From 92ebe8d15b20fb2946eef2c0e18464ebe54fdb2f Mon Sep 17 00:00:00 2001
From: 0xff-dev <stevenshuang521@gmail.com>
Date: Sat, 2 Nov 2024 09:38:37 +0800
Subject: [PATCH] Add solution and test-cases for problem 2490

---
 .../2490.Circular-Sentence/README.md          | 51 ++++++++++++++-----
 .../2490.Circular-Sentence/Solution.go        | 15 +++++-
 .../2490.Circular-Sentence/Solution_test.go   | 12 ++---
 3 files changed, 57 insertions(+), 21 deletions(-)

diff --git a/leetcode/2401-2500/2490.Circular-Sentence/README.md b/leetcode/2401-2500/2490.Circular-Sentence/README.md
index b03d52c8d..68f11317f 100755
--- a/leetcode/2401-2500/2490.Circular-Sentence/README.md
+++ b/leetcode/2401-2500/2490.Circular-Sentence/README.md
@@ -1,28 +1,53 @@
 # [2490.Circular Sentence][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
+A **sentence** is a list of words that are separated by a **single** space with no leading or trailing spaces.
+
+- For example, `"Hello World"`, `"HELLO"`, `"hello world hello world"` are all sentences.
+
+Words consist of **only** uppercase and lowercase English letters. Uppercase and lowercase English letters are considered different.
+
+A sentence is **circular** if:
+
+- The last character of a word is equal to the first character of the next word.
+- The last character of the last word is equal to the first character of the first word.
+
+For example, `"leetcode exercises sound delightful"`, `"eetcode"`, `"leetcode eats soul"` are all circular sentences. However, `"Leetcode is cool"`, `"happy Leetcode"`, `"Leetcode"` and `"I like Leetcode"` are **not** circular sentences.
+
+Given a string `sentence`, return `true` if it is circular. Otherwise, return `false`.
 
 **Example 1:**
 
 ```
-Input: a = "11", b = "1"
-Output: "100"
+Input: sentence = "leetcode exercises sound delightful"
+Output: true
+Explanation: The words in sentence are ["leetcode", "exercises", "sound", "delightful"].
+- leetcode's last character is equal to exercises's first character.
+- exercises's last character is equal to sound's first character.
+- sound's last character is equal to delightful's first character.
+- delightful's last character is equal to leetcode's first character.
+The sentence is circular.
 ```
 
-## 题意
-> ...
-
-## 题解
+**Example 2:**
 
-### 思路1
-> ...
-Circular Sentence
-```go
+```
+Input: sentence = "eetcode"
+Output: true
+Explanation: The words in sentence are ["eetcode"].
+- eetcode's last character is equal to eetcode's first character.
+The sentence is circular.
 ```
 
+**Example 3:**
+
+```
+Input: sentence = "Leetcode is cool"
+Output: false
+Explanation: The words in sentence are ["Leetcode", "is", "cool"].
+- Leetcode's last character is not equal to is's first character.
+The sentence is not circular.
+```
 
 ## 结语
 
diff --git a/leetcode/2401-2500/2490.Circular-Sentence/Solution.go b/leetcode/2401-2500/2490.Circular-Sentence/Solution.go
index d115ccf5e..91057f2c4 100644
--- a/leetcode/2401-2500/2490.Circular-Sentence/Solution.go
+++ b/leetcode/2401-2500/2490.Circular-Sentence/Solution.go
@@ -1,5 +1,16 @@
 package Solution
 
-func Solution(x bool) bool {
-	return x
+func Solution(sentence string) bool {
+	l := len(sentence)
+	if sentence[0] != sentence[l-1] {
+		return false
+	}
+	for i := range sentence {
+		if sentence[i] == ' ' {
+			if sentence[i-1] != sentence[i+1] {
+				return false
+			}
+		}
+	}
+	return true
 }
diff --git a/leetcode/2401-2500/2490.Circular-Sentence/Solution_test.go b/leetcode/2401-2500/2490.Circular-Sentence/Solution_test.go
index 14ff50eb4..68f7b1bc3 100644
--- a/leetcode/2401-2500/2490.Circular-Sentence/Solution_test.go
+++ b/leetcode/2401-2500/2490.Circular-Sentence/Solution_test.go
@@ -10,12 +10,12 @@ func TestSolution(t *testing.T) {
 	//	测试用例
 	cases := []struct {
 		name   string
-		inputs bool
+		inputs string
 		expect bool
 	}{
-		{"TestCase", true, true},
-		{"TestCase", true, true},
-		{"TestCase", false, false},
+		{"TestCase1", "leetcode exercises sound delightful", true},
+		{"TestCase2", "eetcode", true},
+		{"TestCase3", "Leetcode is cool", false},
 	}
 
 	//	开始测试
@@ -30,10 +30,10 @@ func TestSolution(t *testing.T) {
 	}
 }
 
-//	压力测试
+// 压力测试
 func BenchmarkSolution(b *testing.B) {
 }
 
-//	使用案列
+// 使用案列
 func ExampleSolution() {
 }