Add Game of Life exercise (#2793)

* Add Game of Life exercise

* resolve PR reviews

* fix lint markdown issue

CONTRIBUTING.md

@@ -207,6 +207,10 @@ Each problem/submodule has three source sets:
 - `.meta/src/reference/java/` — a reference solution that passes all the tests
 - `src/main/java/` — starter source file(s).
 
+### Update/sync Gradle versions
+
+Please read [How to Update Gradle](../reference/how-to-update-gradle.md)
+
 ## Contributing to Concept Exercises
 
 Please read [Implementing a Concept Exercise](reference/implementing-a-concept-exercise.md).

config.json

@@ -1791,6 +1791,17 @@
           "lists"
         ],
         "difficulty": 10
+      },
+      {
+        "slug": "game-of-life",
+        "name": "Conway's Game of Life",
+        "uuid": "749de7fc-3dcb-4231-9b4f-115d153af74f",
+        "practices": [],
+        "prerequisites": [
+          "arrays",
+          "if-statements"
+        ],
+        "difficulty": 5
       }
     ],
     "foregone": [

exercises/practice/game-of-life/.docs/instructions.md

@@ -0,0 +1,11 @@
+# Instructions
+
+After each generation, the cells interact with their eight neighbors, which are cells adjacent horizontally, vertically, or diagonally.
+
+The following rules are applied to each cell:
+
+- Any live cell with two or three live neighbors lives on.
+- Any dead cell with exactly three live neighbors becomes a live cell.
+- All other cells die or stay dead.
+
+Given a matrix of 1s and 0s (corresponding to live and dead cells), apply the rules to each cell, and return the next generation.

exercises/practice/game-of-life/.docs/introduction.md

@@ -0,0 +1,9 @@
+# Introduction
+
+[Conway's Game of Life][game-of-life] is a fascinating cellular automaton created by the British mathematician John Horton Conway in 1970.
+
+The game consists of a two-dimensional grid of cells that can either be "alive" or "dead."
+
+After each generation, the cells interact with their eight neighbors via a set of rules, which define the new generation.
+
+[game-of-life]: https://en.wikipedia.org/wiki/Conway%27s_Game_of_Life

exercises/practice/game-of-life/.meta/config.json

@@ -0,0 +1,22 @@
+{
+  "authors": [
+    "akbatra567"
+  ],
+  "files": {
+    "solution": [
+      "src/main/java/GameOfLife.java"
+    ],
+    "test": [
+      "src/test/java/GameOfLifeTest.java"
+    ],
+    "example": [
+      ".meta/src/reference/java/GameOfLife.java"
+    ],
+    "invalidator": [
+      "build.gradle"
+    ]
+  },
+  "blurb": "Implement Conway's Game of Life.",
+  "source": "Wikipedia",
+  "source_url": "https://en.wikipedia.org/wiki/Conway%27s_Game_of_Life"
+}

exercises/practice/game-of-life/.meta/src/reference/java/GameOfLife.java

@@ -0,0 +1,37 @@
+class GameOfLife {
+    public int[][] tick(int[][] matrix) {
+        if (matrix.length == 0) {
+            return matrix;
+        }
+        int rowCount = matrix.length;
+        int columnCount = matrix[0].length;
+        int[][] resultMatrix = new int[rowCount][columnCount];
+
+        for (int row = 0; row < rowCount; row++) {
+            for (int column = 0; column < columnCount; column++) {
+                int liveNeighbors = countLiveNeighbors(matrix, row, column);
+
+                if ((matrix[row][column] == 1 && (liveNeighbors == 2 || liveNeighbors == 3)) ||
+                        (matrix[row][column] == 0 && liveNeighbors == 3)) {
+                    resultMatrix[row][column] = 1;
+                }
+            }
+        }
+        return resultMatrix;
+    }
+
+    private int countLiveNeighbors(int[][] matrix, int row, int col) {
+        int rowCount = matrix.length;
+        int columnCount = matrix[0].length;
+        int count = 0;
+
+        for (int i = Math.max(0, row - 1); i <= Math.min(row + 1, rowCount - 1); i++) {
+            for (int j = Math.max(0, col - 1); j <= Math.min(col + 1, columnCount - 1); j++) {
+                if (i != row || j != col) {
+                    count += matrix[i][j];
+                }
+            }
+        }
+        return count;
+    }
+}

exercises/practice/game-of-life/.meta/tests.toml

@@ -0,0 +1,34 @@
+# This is an auto-generated file.
+#
+# Regenerating this file via `configlet sync` will:
+# - Recreate every `description` key/value pair
+# - Recreate every `reimplements` key/value pair, where they exist in problem-specifications
+# - Remove any `include = true` key/value pair (an omitted `include` key implies inclusion)
+# - Preserve any other key/value pair
+#
+# As user-added comments (using the # character) will be removed when this file
+# is regenerated, comments can be added via a `comment` key.
+
+[ae86ea7d-bd07-4357-90b3-ac7d256bd5c5]
+description = "empty matrix"
+
+[4ea5ccb7-7b73-4281-954a-bed1b0f139a5]
+description = "live cells with zero live neighbors die"
+
+[df245adc-14ff-4f9c-b2ae-f465ef5321b2]
+description = "live cells with only one live neighbor die"
+
+[2a713b56-283c-48c8-adae-1d21306c80ae]
+description = "live cells with two live neighbors stay alive"
+
+[86d5c5a5-ab7b-41a1-8907-c9b3fc5e9dae]
+description = "live cells with three live neighbors stay alive"
+
+[015f60ac-39d8-4c6c-8328-57f334fc9f89]
+description = "dead cells with three live neighbors become alive"
+
+[2ee69c00-9d41-4b8b-89da-5832e735ccf1]
+description = "live cells with four or more neighbors die"
+
+[a79b42be-ed6c-4e27-9206-43da08697ef6]
+description = "bigger matrix"

exercises/practice/game-of-life/build.gradle

@@ -0,0 +1,23 @@
+plugins {
+  id "java"
+}
+
+repositories {
+  mavenCentral()
+}
+
+dependencies {
+  testImplementation platform("org.junit:junit-bom:5.10.0")
+  testImplementation "org.junit.jupiter:junit-jupiter"
+  testImplementation "org.assertj:assertj-core:3.25.1"
+}
+
+test {
+  useJUnitPlatform()
+
+  testLogging {
+    exceptionFormat = "full"
+    showStandardStreams = true
+    events = ["passed", "failed", "skipped"]
+  }
+}

exercises/practice/game-of-life/gradle/wrapper/gradle-wrapper.properties

@@ -0,0 +1,6 @@
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.7-bin.zip
+validateDistributionUrl=true
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists