challenge 2d-array

src/2d-array/2d-array.spec.ts

@@ -0,0 +1,23 @@
+import {describe, it, skip} from 'node:test';
+import * as assert from "node:assert";
+import {findHighestHourglassSum} from "./2d-array";
+import {Matrix} from "./matrix";
+describe("2D Array",  () => {
+   describe("findHighestHourglassSum", () => {
+      it("should return 0 if the matrix is empty", () => {
+         assert.equal(findHighestHourglassSum(new Matrix([])), 0);
+      })
+
+      it("should return 19 with this matrix", () => {
+         assert.equal(findHighestHourglassSum(
+             new Matrix([
+                [1, 1, 1, 0, 0, 0],
+                [0, 1, 0, 0, 0, 0],
+                [1, 1, 1, 0, 0, 0],
+                [0, 0, 2, 4, 4, 0],
+                [0, 0, 0, 2, 0, 0],
+                [0, 0, 1, 2, 4, 0]]
+             )), 19);
+      })
+   })
+})

src/2d-array/2d-array.ts

@@ -0,0 +1,18 @@
+import {Matrix} from "./matrix";
+import {Hourglass} from "./hourglass";
+
+export type TwoDimensionVector = Array<number[]>
+
+export function findHighestHourglassSum(matrix: Matrix) {
+    const hourglasses: Hourglass[] = Hourglass.extractFromMatrix(matrix);
+    const sums: number[] = [];
+
+    if(hourglasses.length === 0) {
+        return 0;
+    }
+    for(let i = 0; i < hourglasses.length; i++) {
+        sums.push(hourglasses[i].sum());
+    }
+
+    return Math.max(...sums);
+}

src/2d-array/hourglass.spec.ts

@@ -0,0 +1,76 @@
+import {describe, it, skip} from 'node:test';
+import * as assert from "node:assert";
+import {Hourglass} from "./hourglass";
+import {Matrix} from "./matrix";
+import {TwoDimensionVector} from "./2d-array";
+describe("2D Array", () => {
+   describe("extractFromMatrix", () => {
+      it("should extract the hourglasses matrices", () => {
+          const hourglasses = Hourglass.extractFromMatrix(new Matrix([
+              [1, 1, 1, 0, 0, 0],
+              [0, 1, 0, 0, 0, 0],
+              [1, 1, 1, 0, 0, 0],
+              [0, 0, 2, 4, 4, 0],
+              [0, 0, 0, 2, 0, 0],
+              [0, 0, 1, 2, 4, 0]
+          ]));
+
+          const matrixOfHourglasses: TwoDimensionVector[] = [];
+          hourglasses.forEach(hG => {
+              matrixOfHourglasses.push(hG.items);
+          })
+          assert.deepStrictEqual(matrixOfHourglasses, [
+              [[1, 1, 1], [0, 1, 0], [1, 1, 1]],
+              [[1, 1, 0], [0, 0, 0], [1, 1, 0]],
+              [[1, 0, 0], [0, 0, 0], [1, 0, 0]],
+              [[0, 0, 0], [0, 0, 0], [0, 0, 0]],
+
+              [[0, 1, 0], [0, 1, 0], [0, 0, 2]],
+              [[1, 0, 0], [0, 1, 0], [0, 2, 4]],
+              [[0, 0, 0], [0, 0, 0], [2, 4, 4]],
+              [[0, 0, 0], [0, 0, 0], [4, 4, 0]],
+
+              [[1, 1, 1], [0, 0, 0], [0, 0, 0]],
+              [[1, 1, 0], [0, 2, 0], [0, 0, 2]],
+              [[1, 0, 0], [0, 4, 0], [0, 2, 0]],
+              [[0, 0, 0], [0, 4, 0], [2, 0, 0]],
+
+              [[0, 0, 2], [0, 0, 0], [0, 0, 1]],
+              [[0, 2, 4], [0, 0, 0], [0, 1, 2]],
+              [[2, 4, 4], [0, 2, 0], [1, 2, 4]],
+              [[4, 4, 0], [0, 0, 0], [2, 4, 0]],
+          ])
+      })
+
+      it("should return a single hourglass", () => {
+          const hourglasses = Hourglass.extractFromMatrix(
+              (new Matrix([[1, 1, 1], [1, 1, 1], [1, 1, 1]
+              ])));
+
+          assert.equal(hourglasses.length, 1)
+          assert.deepStrictEqual(hourglasses[0].items, [[1, 1, 1], [0, 1, 0], [1, 1, 1]])
+      })
+
+      it("should return zero hourglass", () => {
+         assert.deepStrictEqual(Hourglass.extractFromMatrix(
+             new Matrix([])), [])
+      })
+
+      it("should return zero hourglass", () => {
+         assert.deepStrictEqual(Hourglass.extractFromMatrix(
+             new Matrix([[1, 2], [3, 4]])), [])
+      })
+   });
+
+   describe("sum", () => {
+         it("should return the sum of every item in an hourglass", () => {
+            assert.equal(new Hourglass([[1, 1, 1], [1, 1, 1], [1, 1, 1]]).sum(),7);
+         })
+   })
+
+   describe("hourglassify", () => {
+      it("should convert a 3x3 matrix in an hourglass", () => {
+         assert.deepStrictEqual(Hourglass.hourglassify([[1, 1, 1], [1, 1, 1], [1, 1, 1]]),[[1, 1, 1], [0, 1, 0], [1, 1, 1]]);
+      })
+   })
+});

src/2d-array/hourglass.ts

@@ -0,0 +1,56 @@
+import {TwoDimensionVector} from "./2d-array";
+import {Matrix} from "./matrix";
+/**
+ * An hourglass is a matrix of numbers with this shape:
+ * a b c   x x x
+ * 0 d 0   0 x 0
+ * e f g   x x x
+ */
+
+export class Hourglass {
+    items: TwoDimensionVector = []
+
+    constructor(items: TwoDimensionVector) {
+        this.items = Hourglass.hourglassify(items);
+    }
+
+    static hourglassify(items: TwoDimensionVector): TwoDimensionVector {
+        items[1][0] = 0;
+        items[1][2] = 0;
+        return items;
+    }
+
+    sum(): number {
+        let sum = 0;
+        this.items.forEach(item => {
+            item.forEach(num => {
+                sum += num;
+            })
+        })
+        return sum;
+    }
+
+    static extractFromMatrix(matrix: Matrix): Hourglass[] {
+        if (matrix.items.length >= 3) {
+            const hourglasses: Hourglass[] = [];
+            let hourglass: Hourglass;
+            const width = matrix.items[0].length;
+            const height = matrix.items.length;
+
+            const maxRightShift = width - 3;
+            const maxTopShift = height - 3;
+
+            for(let tS = 0; tS <= maxTopShift; tS++) {
+                for (let rS = 0; rS <= maxRightShift; rS++) {
+                    hourglasses.push(new Hourglass([
+                        [matrix.items[tS][rS], matrix.items[tS][rS + 1], matrix.items[tS][rS + 2]],
+                        [matrix.items[tS + 1][rS], matrix.items[tS + 1][rS + 1], matrix.items[tS + 1][rS + 2]],
+                        [matrix.items[tS + 2][rS], matrix.items[tS + 2][rS + 1], matrix.items[tS + 2][rS + 2]]]));
+                }
+            }
+            return hourglasses;
+        } else {
+            return [];
+        }
+    }
+}

src/2d-array/matrix.spec.ts

@@ -0,0 +1,4 @@
+import {describe, it, skip} from 'node:test';
+describe("Matrix", () => {
+   skip();
+})

src/2d-array/matrix.ts

@@ -0,0 +1,9 @@
+import {TwoDimensionVector} from "./2d-array";
+
+export class Matrix {
+    items: TwoDimensionVector = []
+
+    constructor(items: TwoDimensionVector) {
+        this.items = items;
+    }
+}

src/repeated-string/repeated-string.spec.ts

@@ -2,6 +2,7 @@ import {describe, it} from 'node:test';
 import * as assert from "node:assert";
 import {countA, countInstanceOfCharInAString} from "./repeated-string";
 
+describe("Repeated String", () => {
     describe("countA", () => {
         it("should return 0 if the s string is empty", (t) => {
             assert.equal(countA("", 0), 0);
@@ -49,3 +50,4 @@ describe("countInstanceOfCharInAString", () => {
             assert.equal(countInstanceOfCharInAString("a", "aaa"), 3);
         })
     })
+});