merge: Create firstRelativeMaxPointInArray.js (#772)

* Create first_relative_max_point_in_array.js

go over randomly generated array and print first spike or maximum point index in it
runs in O(log(n))

* rename file to match requested casing

* add comments

I prefer SOLID standards so that's why didn't add them at first but due to the repository requirements was needed to be added

* remove template unrelated comments

* Update equals check to match JavaScript standards

* create file skafolding and adjust filename to reflect main function

* using newer node version

* add tests

* add last line as empty line

* style changes

* move algorithm tests to test folder

* revert to old package lock file

* chore: add ending line feed

Co-authored-by: Rak Laptudirm <raklaptudirm@gmail.com>

Data-Structures/Array/LocalMaximomPoint.js

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+/**
+ * [LocalMaxima](https://www.geeksforgeeks.org/find-indices-of-all-local-maxima-and-local-minima-in-an-array/) is an algorithm to find relative bigger numbers compared to their neighbors
+ *
+ * Notes:
+ * - works by using divide and conquer
+ * - the function gets the array A with n Real numbersand returns the local max point index (if more than one exists return the first one)
+ *
+ * @complexity: O(log(n)) (on average )
+ * @complexity: O(log(n)) (worst case)
+ * @flow
+ */
+const findMaxPointIndex = (array, rangeStartIndex, rangeEndIndex, originalLength) => {
+  // find index range middle point
+  const middleIndex = rangeStartIndex + parseInt((rangeEndIndex - rangeStartIndex) / 2)
+
+  // handle array bounds
+  if ((middleIndex === 0 || array[middleIndex - 1] <= array[middleIndex]) &&
+        (middleIndex === originalLength - 1 || array[middleIndex + 1] <= array[middleIndex])) {
+    return middleIndex
+  } else if (middleIndex > 0 && array[middleIndex - 1] > array[middleIndex]) {
+    return findMaxPointIndex(array, rangeStartIndex, (middleIndex - 1), originalLength)
+  } else {
+    // regular local max
+    return findMaxPointIndex(array, (middleIndex + 1), rangeEndIndex, originalLength)
+  }
+}
+
+const LocalMaximomPoint = (A) => findMaxPointIndex(A, 0, A.length - 1, A.length)
+
+export { LocalMaximomPoint }

Data-Structures/Array/test/LocalMaximomPoint.test.js

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+import { LocalMaximomPoint } from '../LocalMaximomPoint'
+
+describe('LocalMaximomPoint tests', () => {
+  it('test boundry maximom points - last element', () => {
+    const Array = [1, 2, 3, 4, 5, 6, 12]
+    expect(LocalMaximomPoint(Array)).toEqual(6)
+  })
+
+  it('test boundry maximom points - first element', () => {
+    const Array2 = [13, 6, 5, 4, 3, 2, 1]
+    expect(LocalMaximomPoint(Array2)).toEqual(0)
+  })
+
+  it('test boundry maximom points - should find first maximom point from the top', () => {
+    // Test a mix of number types (i.e., positive/negative, numbers with decimals, fractions)
+    const Array = [13, 2, 3, 4, 5, 6, 12]
+    expect(LocalMaximomPoint(Array)).toEqual(6)
+  })
+
+  it('test inner points - second element', () => {
+    const Array2 = [13, 16, 5, 4, 3, 2, 1]
+    expect(LocalMaximomPoint(Array2)).toEqual(1)
+  })
+
+  it('test inner points - element some where in the middle', () => {
+    const Array2 = [13, 16, 5, 41, 3, 2, 1]
+    expect(LocalMaximomPoint(Array2)).toEqual(3)
+  })
+})