Add 4 array snippets

snippets/transpose.md

@@ -0,0 +1,20 @@
+---
+title: Transpose matrix
+tags: array
+expertise: intermediate
+author: chalarangelo
+firstSeen: 2022-04-20T05:00:00-04:00
+---
+
+Transposes a two-dimensional array.
+
+- Use `Array.prototype.map()` to create the transpose of the given two-dimensional array.
+
+```js
+const transpose = arr => arr[0].map((col, i) => arr.map(row => row[i]));
+```
+
+```js
+transpose([[1, 2, 3], [4, 5, 6], [7, 8, 9], [10, 11, 12]]);
+// [[1, 4, 7, 10], [2, 5, 8, 11], [3, 6, 9, 12]
+```