Merge pull request #838 from 0xff-dev/289

Add solution and test-cases for problem 289

Author: 6boris

leetcode/201-300/0289.Game-of-Life/README.md

@@ -1,28 +1,34 @@
 # [289.Game of Life][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
+According to [Wikipedia's article](https://en.wikipedia.org/wiki/Conway%27s_Game_of_Life): "The **Game of Life**, also known simply as **Life**, is a cellular automaton devised by the British mathematician John Horton Conway in 1970."
+
+The board is made up of an m x n grid of cells, where each cell has an initial state: **live** (represented by a `1`) or **dead** (represented by a `0`). Each cell interacts with its [eight neighbors](https://en.wikipedia.org/wiki/Moore_neighborhood) (horizontal, vertical, diagonal) using the following four rules (taken from the above Wikipedia article):
+
+- Any live cell with fewer than two live neighbors dies as if caused by under-population.
+- Any live cell with two or three live neighbors lives on to the next generation.
+- Any live cell with more than three live neighbors dies, as if by over-population.
+- Any dead cell with exactly three live neighbors becomes a live cell, as if by reproduction.
+
+The next state is created by applying the above rules simultaneously to every cell in the current state, where births and deaths occur simultaneously. Given the current state of the `m x n` grid `board`, return the next state.
 
-**Example 1:**
+**Example 1:**  
+
+![1](./grid1.jpeg)
 
 ```
-Input: a = "11", b = "1"
-Output: "100"
+Input: board = [[0,1,0],[0,0,1],[1,1,1],[0,0,0]]
+Output: [[0,0,0],[1,0,1],[0,1,1],[0,1,0]]
 ```
 
-## 题意
-> ...
+**Example 2:**  
 
-## 题解
+![2](./grid2.jpeg)
 
-### 思路1
-> ...
-Game of Life
-```go
 ```
-
+Input: board = [[1,1],[1,0]]
+Output: [[1,1],[1,1]]
+```
 
 ## 结语
 

leetcode/201-300/0289.Game-of-Life/Solution.go

@@ -1,5 +1,51 @@
 package Solution
 
-func Solution(x bool) bool {
-	return x
+func Solution(board [][]int) {
+	rows, cols := len(board), len(board[0])
+
+	var ones func(int, int) int
+	ones = func(x, y int) int {
+		count := 0
+		for i := -1; i <= 1; i++ {
+			for j := -1; j <= 1; j++ {
+				if i == 0 && j == 0 {
+					continue
+				}
+
+				a, b := x+i, y+j
+				// 1说明之前就是就是活着的，2表示之前是活着的，但是因为周围环境自己死亡
+				if a >= 0 && a < rows && b >= 0 && b < cols && (board[a][b] == 1 || board[a][b] == 2) {
+					count++
+				}
+			}
+		}
+		return count
+	}
+	for r := 0; r < rows; r++ {
+		for c := 0; c < cols; c++ {
+			count := ones(r, c)
+			if count < 2 || count > 3 {
+				if board[r][c] == 1 {
+					// 之前是活着的，但是被迫挂了
+					board[r][c] = 2
+				}
+			}
+
+			// 被迫复活
+			if count == 3 && board[r][c] == 0 {
+				board[r][c] = 3
+			}
+		}
+	}
+	for r := 0; r < rows; r++ {
+		for c := 0; c < cols; c++ {
+			if board[r][c] == 2 {
+				board[r][c] = 0
+			}
+			if board[r][c] == 3 {
+				board[r][c] = 1
+			}
+		}
+	}
+	return
 }

leetcode/201-300/0289.Game-of-Life/Solution_test.go

@@ -10,30 +10,33 @@ func TestSolution(t *testing.T) {
 	//	测试用例
 	cases := []struct {
 		name   string
-		inputs bool
-		expect bool
+		inputs [][]int
+		expect [][]int
 	}{
-		{"TestCase", true, true},
-		{"TestCase", true, true},
-		{"TestCase", false, false},
+		{"TestCase1", [][]int{
+			{0, 1, 0}, {0, 0, 1}, {1, 1, 1}, {0, 0, 0},
+		}, [][]int{
+			{0, 0, 0}, {1, 0, 1}, {0, 1, 1}, {0, 1, 0},
+		}},
+		{"TestCase2", [][]int{{1, 1}, {1, 0}}, [][]int{{1, 1}, {1, 1}}},
 	}
 
 	//	开始测试
 	for i, c := range cases {
 		t.Run(c.name+" "+strconv.Itoa(i), func(t *testing.T) {
-			got := Solution(c.inputs)
-			if !reflect.DeepEqual(got, c.expect) {
+			Solution(c.inputs)
+			if !reflect.DeepEqual(c.inputs, c.expect) {
 				t.Fatalf("expected: %v, but got: %v, with inputs: %v",
-					c.expect, got, c.inputs)
+					c.expect, c.inputs, c.inputs)
 			}
 		})
 	}
 }
 
-//	压力测试
+// 压力测试
 func BenchmarkSolution(b *testing.B) {
 }
 
-//	使用案列
+// 使用案列
 func ExampleSolution() {
 }