diff --git a/01/app.js b/01/app.js
index e69de29..86e93fb 100644
--- a/01/app.js
+++ b/01/app.js
@@ -0,0 +1,8 @@
+const showTime = () => {
+    setInterval(() => {
+        const date = new Date()
+        console.log(date.toLocaleTimeString())
+    }, 1000)
+};
+
+showTime();
\ No newline at end of file
diff --git a/02/app.js b/02/app.js
index e69de29..e981246 100644
--- a/02/app.js
+++ b/02/app.js
@@ -0,0 +1,5 @@
+const sayHello = (name) => {
+    console.log(`Witaj ${name}`)
+}
+
+sayHello("devMentor.pl");
\ No newline at end of file
diff --git a/03/app.js b/03/app.js
index e69de29..bddb3b0 100644
--- a/03/app.js
+++ b/03/app.js
@@ -0,0 +1,9 @@
+const sumNumber = function (n) {
+    let sum = 0;
+    for (let i = 1; i <= n; i++) {
+        sum += i;
+    }
+    return sum
+}
+
+console.log(sumNumber(4));
\ No newline at end of file
diff --git a/04/app.js b/04/app.js
index e69de29..830d088 100644
--- a/04/app.js
+++ b/04/app.js
@@ -0,0 +1,17 @@
+function runTime() {
+    let interval = 0
+    const timeInterval = setInterval(() => {
+        const date = new Date();
+        console.log(date.toLocaleTimeString())
+        interval++
+        
+        if (interval === 5) {
+            clearInterval(timeInterval);
+            console.log("interval przerwany");
+        };
+    }, 5000);
+};
+runTime();
+
+
+