chore: convert functions to an ES2015 classes (#1656)

* chore: convert functions to an ES2015 classes

* remove unnecessary functions

Author: hasanalkaf3

Diff for: Conversions/RailwayTimeConversion.js

@@ -24,8 +24,8 @@ const RailwayTimeConversion = (timeString) => {
   const [hour, minute, secondWithShift] = timeString.split(':')
   // split second and shift value.
   const [second, shift] = [
-    secondWithShift.substr(0, 2),
-    secondWithShift.substr(2)
+    secondWithShift.substring(0, 2),
+    secondWithShift.substring(2)
   ]
   // convert shifted time to not-shift time(Railway time) by using the above explanation.
   if (shift === 'PM') {

Diff for: Data-Structures/Array/Reverse.js

@@ -7,11 +7,9 @@
 
 const Reverse = (arr) => {
   // limit specifies the amount of Reverse actions
-  for (let i = 0, j = arr.length - 1; i < arr.length / 2; i++, j--) {
-    const temp = arr[i]
-    arr[i] = arr[j]
-    arr[j] = temp
-  }
+  for (let i = 0, j = arr.length - 1; i < arr.length / 2; i++, j--)
+    [arr[i], arr[j]] = [arr[j], arr[i]]
+
   return arr
 }
 export { Reverse }

Diff for: Data-Structures/Stack/Stack.js

@@ -8,22 +8,22 @@
 // Functions: push, pop, peek, view, length
 
 // Creates a stack constructor
-const Stack = (function () {
-  function Stack() {
+class Stack {
+  constructor() {
     // The top of the Stack
     this.top = 0
     // The array representation of the stack
     this.stack = []
   }
 
   // Adds a value onto the end of the stack
-  Stack.prototype.push = function (value) {
+  push(value) {
     this.stack[this.top] = value
     this.top++
   }
 
   // Removes and returns the value at the end of the stack
-  Stack.prototype.pop = function () {
+  pop() {
     if (this.top === 0) {
       return 'Stack is Empty'
     }
@@ -35,23 +35,21 @@ const Stack = (function () {
   }
 
   // Returns the size of the stack
-  Stack.prototype.size = function () {
+  size() {
     return this.top
   }
 
   // Returns the value at the end of the stack
-  Stack.prototype.peek = function () {
+  peek() {
     return this.stack[this.top - 1]
   }
 
   // To see all the elements in the stack
-  Stack.prototype.view = function (output = (value) => console.log(value)) {
+  view(output = (value) => console.log(value)) {
     for (let i = 0; i < this.top; i++) {
       output(this.stack[i])
     }
   }
-
-  return Stack
-})()
+}
 
 export { Stack }