Update 3-promise-all.js

02-async-js/hard (promises)/3-promise-all.js

@@ -6,17 +6,47 @@
 
 
 function waitOneSecond() {
-
+    return new Promise((resolve) => {
+        setTimeout(() => {
+            console.log("Resolved after 1 second");
+            resolve();
+        }, 1000);
+    });
 }
 
 function waitTwoSecond() {
-
+    return new Promise((resolve) => {
+        setTimeout(() => {
+            console.log("Resolved after 2 seconds");
+            resolve();
+        }, 2000);
+    });
 }
 
 function waitThreeSecond() {
-
+    return new Promise((resolve) => {
+        setTimeout(() => {
+            console.log("Resolved after 3 seconds");
+            resolve();
+        }, 3000);
+    });
 }
 
-function calculateTime() {
+async function calculateTime() {
+    const startTime = Date.now(); // Record the start time
+
+    // Execute each function sequentially
+    // await waitOneSecond();
+    // await waitTwoSecond();
+    // await waitThreeSecond();
+
+    // Excutes each function using Promise.all
+
+    await Promise.all([waitOneSecond(),waitTwoSecond(),waitThreeSecond()]);
+
+    const endTime = Date.now(); // Record the end time
+    const elapsedTime = endTime - startTime; // Calculate elapsed time in milliseconds
+    console.log(`Total time waited: ${elapsedTime / 1000} seconds`);
+}
 
-}
+calculateTime(); // Call calculateTime function to demonstrate