diff --git a/DesignDataStructure/designI.js b/DesignDataStructure/designI.js
index e3112c5..090eac0 100644
--- a/DesignDataStructure/designI.js
+++ b/DesignDataStructure/designI.js
@@ -21,6 +21,8 @@ The data structure should be efficient enough to accommodate the operations acco
     Frequency: Least frequent. 
 */
 
+/*
+example:
 
 class effStructure {
   this.maxHeap = [];
@@ -33,4 +35,5 @@ class effStructure {
 3) deleteMin(): O(log N)
 4) deleteMax(): O(log N)
 5) Insert(log N)
-6) Delete: O(log N)
\ No newline at end of file
+6) Delete: O(log N)
+*/
\ No newline at end of file
diff --git a/Maximal_square.js b/Maximal_square.js
index 0cb14e8..66da8c8 100644
--- a/Maximal_square.js
+++ b/Maximal_square.js
@@ -25,22 +25,22 @@ Output: 0
 var maximalSquare = function(matrix) {
   var m = matrix.length;
   var n = (matrix[0] || []).length;
-  var dp = Array(m).fill(0).map(_ => Array(n));
+  var dp = Array(m).fill(0).map(() => Array(n));
   var max = 0;
 
   for (var k = 0; k < m; k++) {
-    dp[k][0] = matrix[k][0] === '1' ? 1 : 0;
+    dp[k][0] = matrix[k][0] === "1" ? 1 : 0;
     max = Math.max(max, dp[k][0]);
   }
 
   for (var p = 0; p < n; p++) {
-    dp[0][p] = matrix[0][p] === '1' ? 1 : 0;
+    dp[0][p] = matrix[0][p] === "1" ? 1 : 0;
     max = Math.max(max, dp[0][p]);
   }
 
   for (var i = 1; i < m; i++) {
     for (var j = 1; j < n; j++) {
-      if (matrix[i][j] === '1') {
+      if (matrix[i][j] === "1") {
         dp[i][j] = Math.min(dp[i - 1][j - 1], dp[i - 1][j], dp[i][j - 1]) + 1;
         max = Math.max(max, dp[i][j]);
       } else {
@@ -52,3 +52,5 @@ var maximalSquare = function(matrix) {
   return max * max;
     
 };
+
+module.exports.maximalSquare = maximalSquare;
\ No newline at end of file
diff --git a/Maximal_square_Test.js b/Maximal_square_Test.js
index edadb2b..e5436c5 100644
--- a/Maximal_square_Test.js
+++ b/Maximal_square_Test.js
@@ -1,13 +1,13 @@
-const assert = require('assert');
-const {Maximalsquare } = require('../LeetcodeProblems/Maximal_square');
+const assert = require("assert");
+const {Maximalsquare } = require("../LeetcodeProblems/Maximal_square");
 
 function test1() {
   var matrix = [
     [1, 0, 1, 0, 0],
     [1, 0, 1, 1, 1],
-    [1, 1, 1, 1 1],
+    [1, 1, 1, 1, 1],
     [1, 0, 0, 1, 0],
-  ]
+  ];
 
   assert.strictEqual(Maximalsquare(matrix), 4);
 }
@@ -16,7 +16,7 @@ function test2() {
   var matrix = [
     [0, 1],
     [1,0]
-  ]
+  ];
 
   assert.strictEqual(Maximalsquare(matrix), 1);
 }
@@ -24,8 +24,9 @@ function test2() {
 function test3(){
   var matrix = [
     [0]
-    ]
-   assert.strictEqual(Maximalsquare(matrix), 0);
+  ];
+
+  assert.strictEqual(Maximalsquare(matrix), 0);
 }
   
 function test() {
@@ -34,4 +35,4 @@ function test() {
   test3();
 }
 
-module.exports.test = test
+module.exports.test = test;
diff --git a/SortingAlgorithms/QuickSort.js b/SortingAlgorithms/QuickSort.js
index 69db83b..a6bae1f 100644
--- a/SortingAlgorithms/QuickSort.js
+++ b/SortingAlgorithms/QuickSort.js
@@ -1,39 +1,40 @@
 function swap(items, leftIndex, rightIndex){
-    var temp = items[leftIndex];
-    items[leftIndex] = items[rightIndex];
-    items[rightIndex] = temp;
+  var temp = items[leftIndex];
+  items[leftIndex] = items[rightIndex];
+  items[rightIndex] = temp;
 }
 function partition(items, left, right) {
-    var pivot   = items[Math.floor((right + left) / 2)], //middle element
-        i       = left, //left pointer
-        j       = right; //right pointer
-    while (i <= j) {
-        while (items[i] < pivot) {
-            i++;
-        }
-        while (items[j] > pivot) {
-            j--;
-        }
-        if (i <= j) {
-            swap(items, i, j); //sawpping two elements
-            i++;
-            j--;
-        }
+  var pivot = items[Math.floor((right + left) / 2)], //middle element
+    i       = left, //left pointer
+    j       = right; //right pointer
+  while (i <= j) {
+    while (items[i] < pivot) {
+      i++;
     }
-    return i;
+    while (items[j] > pivot) {
+      j--;
+    }
+    if (i <= j) {
+      swap(items, i, j); //sawpping two elements
+      i++;
+      j--;
+    }
+  }
+  return i;
 }
 
 function quickSort(items, left, right) {
-    var index;
-    if (items.length > 1) {
-        index = partition(items, left, right); //index returned from partition
-        if (left < index - 1) { //more elements on the left side of the pivot
-            quickSort(items, left, index - 1);
-        }
-        if (index < right) { //more elements on the right side of the pivot
-            quickSort(items, index, right);
-        }
+  var index;
+  if (items.length > 1) {
+    index = partition(items, left, right); //index returned from partition
+    if (left < index - 1) { //more elements on the left side of the pivot
+      quickSort(items, left, index - 1);
+    }
+    if (index < right) { //more elements on the right side of the pivot
+      quickSort(items, index, right);
     }
-    return items;
+  }
+  return items;
 }
 
+module.exports.quickSort = quickSort;
diff --git a/SortingAlgorithms/heapSort.js b/SortingAlgorithms/heapSort.js
index bae4570..e846b0d 100644
--- a/SortingAlgorithms/heapSort.js
+++ b/SortingAlgorithms/heapSort.js
@@ -1,16 +1,17 @@
 // Testing Gist
 var heapSort = function(arr) {
   var n = arr.length;
-  for(var i = Math.floor(n/2) - 1; i >= 0; i--)
+  for(let i = Math.floor(n/2) - 1; i >= 0; i--) {
     heapify(arr, n, i);
+  }
 
-  for(var i = n - 1; i >= 0; i--) {
+  for(let i = n - 1; i >= 0; i--) {
     swap(arr, 0, i);
     heapify(arr, i, 0);
   }
 
   return arr;
-}
+};
 
 var heapify = function(arr, n, i) {
   var left = 2 * i + 1;
@@ -32,17 +33,17 @@ var heapify = function(arr, n, i) {
     swap(arr, i, right);
     heapify(arr, n, right);
   }
-}
+};
 
 var swap = function(arr, a, b) {
   var temp = arr[a];
   arr[a] = arr[b];
   arr[b] = temp;
-}
+};
 
 console.log(heapSort([14, 1, 10, 2, 3, 5, 6, 4, 7, 11, 12, 13]));
 console.log(heapSort([]));
 console.log(heapSort([1]));
 console.log(heapSort([2, 1]));
-console.log(heapSort([1,7,2,3,4,1,10,2,3,4,5]))
+console.log(heapSort([1,7,2,3,4,1,10,2,3,4,5]));
 
diff --git a/utilsClasses/ListNodeTestHelper.js b/utilsClasses/ListNodeTestHelper.js
index 2e18a18..cd17e5e 100644
--- a/utilsClasses/ListNodeTestHelper.js
+++ b/utilsClasses/ListNodeTestHelper.js
@@ -1,4 +1,4 @@
-const assert = require('assert');
+const assert = require("assert");
 
 var assertList = function(list, expectedArr) {
   const listlength = list ? list.length() : 0;
@@ -7,6 +7,6 @@ var assertList = function(list, expectedArr) {
     assert.strictEqual(list.val, expectedArr[i]);
     list = list.next;
   }
-}
+};
 
 module.exports.assertList = assertList;
\ No newline at end of file