BoxBlur

Author: PiotrSierant

CodeSignal/js/thecore/BoxBlur.js

@@ -0,0 +1,18 @@
+function solution(image) {
+    const blurred = [];
+
+    for (let row = 1; row < image.length - 1; row++) {
+        blurred.push([]);
+        for (let col = 1; col < image[row].length - 1; col++) {
+            let sum = 0;
+            for (let r = -1; r <= 1; r++) {
+                for (let c = -1; c <= 1; c++) {
+                    sum += image[row + r][col + c];
+                }
+            }
+            blurred[row - 1].push(Math.floor(sum / 9));
+        }
+    }
+
+    return blurred;
+}

CodeSignal/js/thecore/README.md

@@ -1,3 +1,34 @@
+# BoxBlur
+___
+Last night you partied a little too hard. Now there's a black and white photo of you that's about to go viral! You can't let this ruin your reputation, so you want to apply the box blur algorithm to the photo to hide its content.
+
+The pixels in the input image are represented as integers. The algorithm distorts the input image in the following way: Every pixel `x` in the output image has a value equal to the average value of the pixel values from the `3 × 3` square that has its center at `x`, including `x` itself. All the pixels on the border of `x` are then removed.
+
+Return the blurred image as an integer, with the fractions rounded down.
+
+[My solution - Click me and check the whole solution + comments ](https://github.com/PiotrSierant/HTML-CSS-JS/blob/main/CodeSignal/js/thecore/BoxBlur.js)
+```javascript
+function solution(image) {
+    const blurred = [];
+    
+    for (let row = 1; row < image.length - 1; row++) {
+        blurred.push([]);
+        for (let col = 1; col < image[row].length - 1; col++) {
+            let sum = 0;
+            for (let r = -1; r <= 1; r++) {
+                for (let c = -1; c <= 1; c++) {
+                    sum += image[row + r][col + c];
+                }
+            }
+            blurred[row - 1].push(Math.floor(sum / 9));
+        }
+    }
+    
+    return blurred;
+}
+
+```
+
 # Minesweeper
 ___
 In the popular Minesweeper game you have a board with some mines and those cells that don't contain a mine have a number in it that indicates the total number of mines in the neighboring cells. Starting off with some arrangement of mines we want to create a Minesweeper game setup.