diff --git a/src/algorithms/sorting/shell-sort/ShellSort.js b/src/algorithms/sorting/shell-sort/ShellSort.js
index 6113bc36..58859acb 100644
--- a/src/algorithms/sorting/shell-sort/ShellSort.js
+++ b/src/algorithms/sorting/shell-sort/ShellSort.js
@@ -12,20 +12,20 @@ export default class ShellSort extends Sort {
     while (gap > 0) {
       // Go and compare all distant element pairs.
       for (let i = 0; i < (array.length - gap); i += 1) {
-        let currentIndex = i;
+        let j = i;
         let gapShiftedIndex = i + gap;
 
-        while (currentIndex >= 0) {
+        while (j >= 0) {
           // Call visiting callback.
-          this.callbacks.visitingCallback(array[currentIndex]);
+          this.callbacks.visitingCallback(array[j]);
 
           // Compare and swap array elements if needed.
-          if (this.comparator.lessThan(array[gapShiftedIndex], array[currentIndex])) {
-            [array[currentIndex], array[gapShiftedIndex]] = [array[gapShiftedIndex], array[currentIndex]];
+          if (this.comparator.lessThan(array[gapShiftedIndex], array[j])) {
+            [array[j], array[gapShiftedIndex]] = [array[gapShiftedIndex], array[j]];
           }
 
-          gapShiftedIndex = currentIndex;
-          currentIndex -= gap;
+          gapShiftedIndex = j;
+          j -= gap;
         }
       }
 
diff --git a/src/data-structures/heap/Heap.js b/src/data-structures/heap/Heap.js
index b3ae7068..e12b7afc 100644
--- a/src/data-structures/heap/Heap.js
+++ b/src/data-structures/heap/Heap.js
@@ -95,7 +95,8 @@ export default class Heap {
    * @param {number} indexTwo
    */
   swap(indexOne, indexTwo) {
-    [this.heapContainer[indexOne], this.heapContainer[indexTwo]] = [this.heapContainer[indexTwo], this.heapContainer[indexOne]];
+    [this.heapContainer[indexOne], this.heapContainer[indexTwo]] = [
+      this.heapContainer[indexTwo], this.heapContainer[indexOne]];
   }
 
   /**