Add solution and test-cases for problem 3021

Author: 0xff-dev

leetcode/3001-3100/3021.Alice-and-Bob-Playing-Flower-Game/1.png

@@ -1,28 +1,39 @@
 # [3021.Alice and Bob Playing Flower Game][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
+Alice and Bob are playing a turn-based game on a field, with two lanes of flowers between them. There are `x` flowers in the first lane between Alice and Bob, and `y` flowers in the second lane between them.
+
+![1](./1.png)
+
+The game proceeds as follows:
+
+1. Alice takes the first turn.
+2. In each turn, a player must choose either one of the lane and pick one flower from that side.
+3. At the end of the turn, if there are no flowers left at all, the current player captures their opponent and wins the game.
+
+Given two integers, `n` and `m`, the task is to compute the number of possible pairs `(x, y)` that satisfy the conditions:
+
+- Alice must win the game according to the described rules.
+- The number of flowers `x` in the first lane must be in the range `[1,n]`.
+- The number of flowers `y` in the second lane must be in the range `[1,m]`.
+
+Return the number of possible pairs `(x, y)` that satisfy the conditions mentioned in the statement.
 
 **Example 1:**
 
 ```
-Input: a = "11", b = "1"
-Output: "100"
+Input: n = 3, m = 2
+Output: 3
+Explanation: The following pairs satisfy conditions described in the statement: (1,2), (3,2), (2,1).
 ```
 
-## 题意
-> ...
-
-## 题解
+**Example 2:**
 
-### 思路1
-> ...
-Alice and Bob Playing Flower Game
-```go
 ```
-
+Input: n = 1, m = 1
+Output: 0
+Explanation: No pairs satisfy the conditions described in the statement.
+```
 
 ## 结语
 

leetcode/3001-3100/3021.Alice-and-Bob-Playing-Flower-Game/README.md

@@ -1,5 +1,5 @@
 package Solution
 
-func Solution(x bool) bool {
-	return x
+func Solution(n int, m int) int64 {
+	return int64(m) * int64(n) / 2
 }

leetcode/3001-3100/3021.Alice-and-Bob-Playing-Flower-Game/Solution.go

@@ -10,30 +10,29 @@ func TestSolution(t *testing.T) {
 	//	测试用例
 	cases := []struct {
 		name   string
-		inputs bool
-		expect bool
+		n, m   int
+		expect int64
 	}{
-		{"TestCase", true, true},
-		{"TestCase", true, true},
-		{"TestCase", false, false},
+		{"TestCase1", 3, 2, 3},
+		{"TestCase1", 1, 1, 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.n, c.m)
 			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.n, c.m)
 			}
 		})
 	}
 }
 
-//	压力测试
+// 压力测试
 func BenchmarkSolution(b *testing.B) {
 }
 
-//	使用案列
+// 使用案列
 func ExampleSolution() {
 }