diff --git a/W1/helloworld/HelloWorld.class b/W1/helloworld/HelloWorld.class
new file mode 100644
index 0000000..d968a71
Binary files /dev/null and b/W1/helloworld/HelloWorld.class differ
diff --git a/W1/helloworld/HelloWorld.java b/W1/helloworld/HelloWorld.java
new file mode 100644
index 0000000..8b20ecc
--- /dev/null
+++ b/W1/helloworld/HelloWorld.java
@@ -0,0 +1,5 @@
+public class HelloWorld {
+    public static void main(String[] args) {
+        System.out.println("Hello World!");
+    }
+}
\ No newline at end of file
diff --git a/W1/helloworld/README.md b/W1/helloworld/README.md
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+++ b/W1/helloworld/README.md
@@ -0,0 +1,2 @@
+# java
+