Add 4 array snippets

snippets/closest.md

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+---
+title: Closest numeric match
+tags: math,array
+expertise: intermediate
+author: chalarangelo
+firstSeen: 2022-03-30T05:00:00-04:00
+---
+
+Finds the closest number from an array.
+
+- Use `Array.prototype.reduce()` to scan all elements of the array.
+- Use `Math.abs()` to compare each element's distance from the target value, storing the closest match.
+
+```js
+const closest = (arr, n) =>
+  arr.reduce((acc, num) => (Math.abs(num - n) < Math.abs(acc - n) ? num : acc));
+```
+
+```js
+closest([6, 1, 3, 7, 9], 5); // 6
+```

snippets/findConsecutive.md

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+---
+title: Arrays of consecutive elements
+tags: array
+expertise: intermediate
+author: chalarangelo
+firstSeen: 2022-04-06T05:00:00-04:00
+---
+
+Finds all arrays of consecutive elements.
+
+- Use `Array.prototype.slice()` to create an array with `n - 1` elements removed from the start.
+- Use `Array.prototype.map()` and `Array.prototype.slice()` to map each element to an array of `n` consecutive elements.
+
+```js
+const findConsecutive = (arr, n) =>
+  arr.slice(n - 1).map((v, i) => arr.slice(i, i + n));
+```
+
+```js
+findConsecutive([1, 2, 3, 4, 5], 2);
+// [[1, 2], [2, 3], [3, 4], [4, 5]]
+```

snippets/ranking.md

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+---
+title: Array ranking
+tags: array,math
+expertise: intermediate
+author: chalarangelo
+firstSeen: 2022-04-13T05:00:00-04:00
+---
+
+Calculates the ranking of an array based on a comparator function.
+
+- Use `Array.prototype.map()` and `Array.prototype.filter()` to map each element to a rank using the provided comparator function.
+
+```js
+const ranking = (arr, compFn) =>
+  arr.map(a => arr.filter(b => compFn(a, b)).length + 1);
+```
+
+```js
+ranking([8, 6, 9, 5], (a, b) => a < b);
+// [2, 3, 1, 4]
+ranking(['c', 'a', 'b', 'd'], (a, b) => a.localeCompare(b) > 0);
+// [3, 1, 2, 4]
+```

snippets/transpose.md

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+---
+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]
+```