added debounce solution

Author: namitmalasi

frontend masters/debounce.js

@@ -0,0 +1,18 @@
+function debounce(fn, delay) {
+  let timer;
+  return function () {
+    if (timer) {
+      clearTimeout(timer);
+    }
+    timer = setTimeout(() => {
+      fn.apply(this, arguments);
+      timer = null;
+    }, delay);
+  };
+}
+
+const getData = () => {
+  console.log("calling...");
+};
+
+debounce(getData, 500);

frontend masters/phonescreen/phonescreen.js

@@ -37,3 +37,4 @@ class Foods {
 
 const foods = new Foods(rootElement, foodData);
 foods.renderList();
+