added GridGetX and GridGetY

DIRECTORY.md

@@ -68,6 +68,8 @@
   * [Fibonacci](https://github.com/TheAlgorithms/Javascript/blob/master/Maths/Fibonacci.js)
   * [FindHcf](https://github.com/TheAlgorithms/Javascript/blob/master/Maths/FindHcf.js)
   * [FindLcm](https://github.com/TheAlgorithms/Javascript/blob/master/Maths/FindLcm.js)
+  * [GridGetX](https://github.com/TheAlgorithms/Javascript/blob/master/Maths/GridGetX.js)
+  * [GridGetY](https://github.com/TheAlgorithms/Javascript/blob/master/Maths/GridGetY.js)
   * [Palindrome](https://github.com/TheAlgorithms/Javascript/blob/master/Maths/Palindrome.js)
   * [PascalTriangle](https://github.com/TheAlgorithms/Javascript/blob/master/Maths/PascalTriangle.js)
   * [PiApproximationMonteCarlo](https://github.com/TheAlgorithms/Javascript/blob/master/Maths/PiApproximationMonteCarlo.js)

Maths/GridGetX.js

@@ -0,0 +1,20 @@
+/*
+    author: TangibleDream
+    license: GPL-3.0 or later
+
+    This script will find x given the element and columns for a 2 dimensional array.
+
+    If your array is a perfect square, you can find columns by getting the square
+    root of the length of the array.
+
+*/
+
+const gridGetX = (columns, index) => {
+  while ((index + 1) > columns) {
+    index = index - columns
+  }
+  return (index + 1)
+}
+
+console.log(`If a square array has 400 elements,  then the value of x for the 27th element is ${gridGetX(Math.sqrt(400), 27)}`)
+console.log(`If an array has 7 columns and 3 rows,  then the value of x for the 11th element is ${gridGetX(7, 11)}`)

Maths/GridGetY.js

@@ -0,0 +1,17 @@
+/*
+    author: TangibleDream
+    license: GPL-3.0 or later
+
+    This script will find y given the element and columns for a 2 dimensional array.
+
+    If your array is a perfect square, you can find columns by getting the square
+    root of the length of the array.
+
+*/
+
+const gridGetY = (columns, index) => {
+  return (Math.floor(index / columns)) + 1
+}
+
+console.log(`If a square array has 400 elements,  then the value of y for the 27th element is ${gridGetY(Math.sqrt(400), 27)}`)
+console.log(`If an array has 7 columns and 3 rows,  then the value of y for the 11th element is ${gridGetY(7, 11)}`)