javascript-task intersection a built-in method

Author: Nataliia74

Sprint-1/JavaScript/findCommonItems/findCommonItems.js

@@ -9,6 +9,21 @@
  * @param {Array} secondArray - Second array to compare
  * @returns {Array} Array containing unique common items
  */
-export const findCommonItems = (firstArray, secondArray) => [
-  ...new Set(firstArray.filter((item) => secondArray.includes(item))),
-];
+
+// export const findCommonItems = (firstArray, secondArray) => [
+//   ...new Set(firstArray.filter((item) => secondArray.includes(item))),
+// ];
+
+export const findCommonItems = (firstArray, secondArray) => {
+  const firstArr = new Set(firstArray);
+  const secondArr = new Set(secondArray);
+
+  // return [...firstArr].filter((arr) => secondArr.has(arr));
+  return [...firstArr.intersection(secondArr)];
+};
+
+//  * https://www.w3schools.com/js/js_set_methods.asp#mark_set_new
+//  * Time Complexity: O(m+n)
+//  * Space Complexity: O(m+n)
+//  * Optimal Time Complexity: O(m+n)
+>>>>>>> 4541adf (intersection a built-in method)