Rename js snippets

snippets/js/s/array-similarity.md

@@ -0,0 +1,21 @@
+---
+title: Array similarity
+type: snippet
+language: javascript
+tags: [array,math]
+cover: dark-leaves-5
+dateModified: 2020-10-22T20:24:30+03:00
+---
+
+Returns an array of elements that appear in both arrays.
+
+- Use `Array.prototype.includes()` to determine values that are not part of `values`.
+- Use `Array.prototype.filter()` to remove them.
+
+```js
+const similarity = (arr, values) => arr.filter(v => values.includes(v));
+```
+
+```js
+similarity([1, 2, 3], [1, 2, 4]); // [1, 2]
+```