algorithm: Minesweeper (#1129)

Author: IcarusTheFly

Search/Minesweeper.js

@@ -0,0 +1,38 @@
+/*
+ * Author: IcarusTheFly (https://github.com/IcarusTheFly)
+ * Minesweeper explanation can be found in: https://en.wikipedia.org/wiki/Minesweeper_(video_game)
+ * This function will take a rectangular matrix filled with boolean values - the value for a cell
+ * with a mine will be true, otherwise it will be false.
+ * As a result it will return a rectangular matrix where each cell will have an integer that
+ * counts all the mines in the adjacent cells
+ * Two cells should share at least one corner to be considered adjacent
+ */
+
+/**
+ * @function minesweeper
+ * @description It counts the amount of mines surrounding every cell and returns a formatted matrix
+ * @param {boolean[][]} matrix
+ * @returns {number[][]} Matrix of numbers with the amount of mines surrounding each cell
+ */
+
+export const minesweeper = (matrix) => {
+  const arrResult = []
+  for (let x = 0; x < matrix.length; x++) {
+    const arrLine = []
+    for (let y = 0; y < matrix[x].length; y++) {
+      let minesInCell = 0
+      for (let xi = x - 1; xi <= x + 1; xi++) {
+        if (matrix[xi] !== undefined) {
+          for (let yi = y - 1; yi <= y + 1; yi++) {
+            if ((xi !== x || yi !== y) && matrix[xi][yi] === true) {
+              minesInCell++
+            }
+          }
+        }
+      }
+      arrLine.push(minesInCell)
+    }
+    arrResult.push(arrLine)
+  }
+  return arrResult
+}

Search/test/Minesweeper.test.js

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+import { minesweeper } from '../Minesweeper'
+
+describe('Testing minesweeper function', () => {
+  it('should return the expected 3x3 array', () => {
+    const input = [
+      [true, false, false],
+      [false, true, false],
+      [false, false, false]
+    ]
+    const expectedOutput = [
+      [1, 2, 1],
+      [2, 1, 1],
+      [1, 1, 1]
+    ]
+    expect(minesweeper(input)).toStrictEqual(expectedOutput)
+  })
+
+  it('should return the expected 3x4 array', () => {
+    const input = [
+      [true, false, false, true],
+      [false, false, true, false],
+      [true, true, false, true]
+    ]
+    const expectedOutput = [
+      [0, 2, 2, 1],
+      [3, 4, 3, 3],
+      [1, 2, 3, 1]
+    ]
+    expect(minesweeper(input)).toStrictEqual(expectedOutput)
+  })
+
+  it('should return the expected 5x2 array', () => {
+    const input = [
+      [true, false],
+      [true, false],
+      [false, true],
+      [false, false],
+      [false, false]
+    ]
+    const expectedOutput = [
+      [1, 2],
+      [2, 3],
+      [2, 1],
+      [1, 1],
+      [0, 0]
+    ]
+    expect(minesweeper(input)).toStrictEqual(expectedOutput)
+  })
+
+  it('should return the correct result when there are no mines', () => {
+    const input = [
+      [false, false, false],
+      [false, false, false]
+    ]
+    const expectedOutput = [
+      [0, 0, 0],
+      [0, 0, 0]
+    ]
+    expect(minesweeper(input)).toStrictEqual(expectedOutput)
+  })
+
+  it('should return the correct result when there are mines in every cell', () => {
+    const input = [
+      [true, true, true],
+      [true, true, true],
+      [true, true, true]
+    ]
+    const expectedOutput = [
+      [3, 5, 3],
+      [5, 8, 5],
+      [3, 5, 3]
+    ]
+    expect(minesweeper(input)).toStrictEqual(expectedOutput)
+  })
+})