@@ -10,12 +10,18 @@ import Comparator from '../../../utils/comparator/Comparator';
1010 */
1111
1212export default function binarySearch ( sortedArray , seekElement , comparatorCallback ) {
13+ // Let's create comparator from the comparatorCallback function.
14+ // Comparator object will give us common comparison methods like equal() and lessThen().
1315const comparator = new Comparator ( comparatorCallback ) ;
1416
17+ // These two indices will contain current array (sub-array) boundaries.
1518let startIndex = 0 ;
1619let endIndex = sortedArray . length - 1 ;
1720
21+ // Let's continue to split array until boundaries are collapsed
22+ // and there is nothing to split anymore.
1823while ( startIndex <= endIndex ) {
24+ // Let's calculate the index of the middle element.
1925const middleIndex = startIndex + Math . floor ( ( endIndex - startIndex ) / 2 ) ;
2026
2127// If we've found the element just return its position.
@@ -33,5 +39,6 @@ export default function binarySearch(sortedArray, seekElement, comparatorCallbac
3339}
3440}
3541
42+ // Return -1 if we have not found anything.
3643return - 1 ;
3744}