solution

Author: hecateKat

.github/workflows/ci.yml

@@ -7,12 +7,12 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
         with:
           ref: ${{github.event.pull_request.head.ref}}
           repository: ${{github.event.pull_request.head.repo.full_name}}
       - name: Set up JDK 17
-        uses: actions/setup-java@v2
+        uses: actions/setup-java@v4
         with:
           java-version: '17'
           distribution: 'adopt'

src/main/java/core/basesyntax/Main.java

@@ -1,10 +1,13 @@
 package core.basesyntax;
 
 public class Main {
-    public static void main(String[] args) {
+    public static void main(String[] args) throws InterruptedException {
         Counter counter = new Counter(20);
         for (int i = 1; i <= 20; i++) {
-            new MyThread(counter, String.valueOf(i)).start();
+            MyThread myThread = new MyThread(counter, String.valueOf(i));
+
+            myThread.start();
+            myThread.join();
         }
     }
 }