diff --git a/src/main/java/dev/miti99/lotterygenerator/LotteryGenerator.java b/src/main/java/dev/miti99/lotterygenerator/LotteryGenerator.java
index 1172375..4588185 100644
--- a/src/main/java/dev/miti99/lotterygenerator/LotteryGenerator.java
+++ b/src/main/java/dev/miti99/lotterygenerator/LotteryGenerator.java
@@ -3,6 +3,6 @@ package dev.miti99.lotterygenerator;
 import java.util.List;
 
 public interface LotteryGenerator {
-    List<Integer> generateNumbers();
-    List<Integer> generateNumbers(int numNumber);
+
+  List<Integer> generateNumbers(int numNumber);
 }
diff --git a/src/main/java/dev/miti99/lotterygenerator/Main.java b/src/main/java/dev/miti99/lotterygenerator/Main.java
index 6ca342c..8075974 100644
--- a/src/main/java/dev/miti99/lotterygenerator/Main.java
+++ b/src/main/java/dev/miti99/lotterygenerator/Main.java
@@ -1,7 +1,12 @@
 package dev.miti99.lotterygenerator;
 
+import dev.miti99.lotterygenerator.mega.Mega645Generator;
+
 public class Main {
-    public static void main(String[] args) {
-        System.out.println("Hello world!");
-    }
+
+  public static void main(String[] args) {
+    var generator = new Mega645Generator();
+    var result = generator.generateNumbers(4);
+    System.out.println(result);
+  }
 }
diff --git a/src/main/java/dev/miti99/lotterygenerator/mega/BasePresetGenerator.java b/src/main/java/dev/miti99/lotterygenerator/mega/BasePresetGenerator.java
new file mode 100644
index 0000000..8c3755c
--- /dev/null
+++ b/src/main/java/dev/miti99/lotterygenerator/mega/BasePresetGenerator.java
@@ -0,0 +1,17 @@
+package dev.miti99.lotterygenerator.mega;
+
+import java.util.List;
+
+public class BasePresetGenerator extends MegaGenerator {
+
+  int numNumber;
+
+  public BasePresetGenerator(int minNumber, int maxNumber, int numNumber) {
+    super(minNumber, maxNumber);
+    this.numNumber = numNumber;
+  }
+
+  public List<Integer> generateNumbers() {
+    return generateNumbers(numNumber);
+  }
+}
diff --git a/src/main/java/dev/miti99/lotterygenerator/mega/Mega645Generator.java b/src/main/java/dev/miti99/lotterygenerator/mega/Mega645Generator.java
index 3168ba9..0dd89bc 100644
--- a/src/main/java/dev/miti99/lotterygenerator/mega/Mega645Generator.java
+++ b/src/main/java/dev/miti99/lotterygenerator/mega/Mega645Generator.java
@@ -1,12 +1,12 @@
 package dev.miti99.lotterygenerator.mega;
 
-public class Mega645Generator extends MegaGenerator {
+public class Mega645Generator extends BasePresetGenerator {
 
-    public Mega645Generator(int numNumber) {
-        super(1, 45, numNumber);
-    }
+  public Mega645Generator(int numNumber) {
+    super(1, 45, numNumber);
+  }
 
-    public Mega645Generator() {
-        this(6);
-    }
+  public Mega645Generator() {
+    this(6);
+  }
 }
diff --git a/src/main/java/dev/miti99/lotterygenerator/mega/Mega655Generator.java b/src/main/java/dev/miti99/lotterygenerator/mega/Mega655Generator.java
index a014b5f..fd82f7b 100644
--- a/src/main/java/dev/miti99/lotterygenerator/mega/Mega655Generator.java
+++ b/src/main/java/dev/miti99/lotterygenerator/mega/Mega655Generator.java
@@ -1,12 +1,12 @@
 package dev.miti99.lotterygenerator.mega;
 
-public class Mega655Generator extends MegaGenerator {
+public class Mega655Generator extends BasePresetGenerator {
 
-    public Mega655Generator(int numNumber) {
-        super(1, 55, numNumber);
-    }
+  public Mega655Generator(int numNumber) {
+    super(1, 55, numNumber);
+  }
 
-    public Mega655Generator() {
-        this(6);
-    }
+  public Mega655Generator() {
+    this(6);
+  }
 }
diff --git a/src/main/java/dev/miti99/lotterygenerator/mega/MegaGenerator.java b/src/main/java/dev/miti99/lotterygenerator/mega/MegaGenerator.java
index 273412c..42d6d28 100644
--- a/src/main/java/dev/miti99/lotterygenerator/mega/MegaGenerator.java
+++ b/src/main/java/dev/miti99/lotterygenerator/mega/MegaGenerator.java
@@ -1,45 +1,39 @@
 package dev.miti99.lotterygenerator.mega;
 
 import dev.miti99.lotterygenerator.LotteryGenerator;
-
 import java.util.ArrayList;
 import java.util.List;
 import java.util.stream.Collectors;
 import java.util.stream.IntStream;
 
-public abstract class MegaGenerator implements LotteryGenerator {
-    int minNumber;
-    int maxNumber;
-    int numNumber;
+public class MegaGenerator implements LotteryGenerator {
 
-    public MegaGenerator(int minNumber, int maxNumber, int numNumber) {
-        this.minNumber = minNumber;
-        this.maxNumber = maxNumber;
-        this.numNumber = numNumber;
-    }
+  int minNumber;
+  int maxNumber;
 
-    protected int getTotalNumber() {
-        return maxNumber - minNumber + 1;
-    }
 
-    protected List<Integer> generateBaseNumbers() {
-        return IntStream.rangeClosed(minNumber, maxNumber).boxed().collect(Collectors.toList());
-    }
+  public MegaGenerator(int minNumber, int maxNumber) {
+    this.minNumber = minNumber;
+    this.maxNumber = maxNumber;
+  }
 
-    @Override
-    public List<Integer> generateNumbers(int numNumber) {
-        var baseNumbers = generateBaseNumbers();
-        var result = new ArrayList<Integer>(numNumber);
-        for (int i = 0; i < numNumber; i++) {
-            var index = (int) (Math.random() * baseNumbers.size());
-            result.add(baseNumbers.get(index));
-            baseNumbers.remove(index);
-        }
-        return result;
-    }
+  protected int getTotalNumber() {
+    return maxNumber - minNumber + 1;
+  }
 
-    @Override
-    public List<Integer> generateNumbers() {
-        return generateNumbers(numNumber);
+  protected List<Integer> generateBaseNumbers() {
+    return IntStream.rangeClosed(minNumber, maxNumber).boxed().collect(Collectors.toList());
+  }
+
+  @Override
+  public List<Integer> generateNumbers(int numNumber) {
+    var baseNumbers = generateBaseNumbers();
+    var result = new ArrayList<Integer>(numNumber);
+    for (int i = 0; i < numNumber; i++) {
+      var index = (int) (Math.random() * baseNumbers.size());
+      result.add(baseNumbers.get(index));
+      baseNumbers.remove(index);
     }
+    return result;
+  }
 }
diff --git a/src/main/java/dev/miti99/lotterygenerator/mega/reverserd/ReversedMega645Generator.java b/src/main/java/dev/miti99/lotterygenerator/mega/reverserd/ReversedMega645Generator.java
index 2a1b3b1..4994284 100644
--- a/src/main/java/dev/miti99/lotterygenerator/mega/reverserd/ReversedMega645Generator.java
+++ b/src/main/java/dev/miti99/lotterygenerator/mega/reverserd/ReversedMega645Generator.java
@@ -2,11 +2,11 @@ package dev.miti99.lotterygenerator.mega.reverserd;
 
 public class ReversedMega645Generator extends ReversedMegaGenerator {
 
-    public ReversedMega645Generator(int numNumber) {
-        super(1, 45, numNumber);
-    }
+  public ReversedMega645Generator(int numNumber) {
+    super(1, 45, numNumber);
+  }
 
-    public ReversedMega645Generator() {
-        this(6);
-    }
+  public ReversedMega645Generator() {
+    this(6);
+  }
 }
diff --git a/src/main/java/dev/miti99/lotterygenerator/mega/reverserd/ReversedMega655Generator.java b/src/main/java/dev/miti99/lotterygenerator/mega/reverserd/ReversedMega655Generator.java
index fa5655c..39e59ae 100644
--- a/src/main/java/dev/miti99/lotterygenerator/mega/reverserd/ReversedMega655Generator.java
+++ b/src/main/java/dev/miti99/lotterygenerator/mega/reverserd/ReversedMega655Generator.java
@@ -2,11 +2,11 @@ package dev.miti99.lotterygenerator.mega.reverserd;
 
 public class ReversedMega655Generator extends ReversedMegaGenerator {
 
-    public ReversedMega655Generator(int numNumber) {
-        super(1, 55, numNumber);
-    }
+  public ReversedMega655Generator(int numNumber) {
+    super(1, 55, numNumber);
+  }
 
-    public ReversedMega655Generator() {
-        this(6);
-    }
+  public ReversedMega655Generator() {
+    this(6);
+  }
 }
diff --git a/src/main/java/dev/miti99/lotterygenerator/mega/reverserd/ReversedMegaGenerator.java b/src/main/java/dev/miti99/lotterygenerator/mega/reverserd/ReversedMegaGenerator.java
index 87a3d14..62ef1c8 100644
--- a/src/main/java/dev/miti99/lotterygenerator/mega/reverserd/ReversedMegaGenerator.java
+++ b/src/main/java/dev/miti99/lotterygenerator/mega/reverserd/ReversedMegaGenerator.java
@@ -1,18 +1,18 @@
 package dev.miti99.lotterygenerator.mega.reverserd;
 
-import dev.miti99.lotterygenerator.mega.MegaGenerator;
-
+import dev.miti99.lotterygenerator.mega.BasePresetGenerator;
 import java.util.List;
 
-public class ReversedMegaGenerator extends MegaGenerator {
-    public ReversedMegaGenerator(int minNumber, int maxNumber, int numNumber) {
-        super(minNumber, maxNumber, numNumber);
-    }
+public class ReversedMegaGenerator extends BasePresetGenerator {
 
-    @Override
-    public List<Integer> generateNumbers(int numNumber) {
-        var baseNumbers = generateBaseNumbers();
-        var removedNumbers = super.generateNumbers(getTotalNumber() - numNumber);
-        return baseNumbers.stream().filter(n -> !removedNumbers.contains(n)).toList();
-    }
+  public ReversedMegaGenerator(int minNumber, int maxNumber, int numNumber) {
+    super(minNumber, maxNumber, numNumber);
+  }
+
+  @Override
+  public List<Integer> generateNumbers(int numNumber) {
+    var baseNumbers = generateBaseNumbers();
+    var removedNumbers = super.generateNumbers(getTotalNumber() - numNumber);
+    return baseNumbers.stream().filter(n -> !removedNumbers.contains(n)).toList();
+  }
 }