diff --git a/W1/helloworld b/W1/helloworld
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--- a/W1/helloworld
+++ /dev/null
@@ -1 +0,0 @@
-Subproject commit 52ff456dd9b352bacc80e7cd82da21e90b1bb5ba
diff --git a/W1/helloworld/HelloWorld.class b/W1/helloworld/HelloWorld.class
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index 0000000..d968a71
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diff --git a/W1/helloworld/HelloWorld.java b/W1/helloworld/HelloWorld.java
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--- /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
+