From 7704486f5bf2d40757deef9ff0bedcdb96c43c28 Mon Sep 17 00:00:00 2001
From: happymeal2024 <v.morawski@gmx.de>
Date: Mon, 28 Apr 2025 13:43:27 +0200
Subject: [PATCH] Bubblesort overworked und MergeSort

---
 .../main/java/de/vivi/list/BubbleSort.java    | 25 +++------
 list/src/main/java/de/vivi/list/Main.java     | 20 +++----
 .../src/main/java/de/vivi/list/MergeSort.java | 53 +++++++++++++++++++
 3 files changed, 72 insertions(+), 26 deletions(-)
 create mode 100644 list/src/main/java/de/vivi/list/MergeSort.java

diff --git a/list/src/main/java/de/vivi/list/BubbleSort.java b/list/src/main/java/de/vivi/list/BubbleSort.java
index c1e7506..76aa0dc 100644
--- a/list/src/main/java/de/vivi/list/BubbleSort.java
+++ b/list/src/main/java/de/vivi/list/BubbleSort.java
@@ -1,28 +1,19 @@
 package de.vivi.list;
 
-import java.util.Arrays;
-
 public class BubbleSort implements ByteSort {
 
-
-    private byte bubbleTemp;
-    private int a;
-
     @Override
     public ByteList sort(ByteList list) {
+        int n = list.size();
 
-        while (a < list.size() * list.size()) {
-            for (int i = 0; i < list.size() - 1; i++) {
-                if (list.get(i + 1) < list.get(i)) {
-                    bubbleTemp = list.get(i + 1);
-                    list.set(i + 1, list.get(i));
-                    list.set(i, bubbleTemp);
+        for (int i = 0; i < n - 1; i++)
+            for (int j = 0; j < n - i - 1; j++)
+                if (list.get(j) > list.get(j + 1)) {
+                    byte temp = list.get(j);
+                    list.set(j, list.get(j + 1));
+                    list.set(j + 1, temp);
                 }
-                a++;
-            }
-        }
-        System.out.println(a + " Anzahl runden");
-        
+
         return list;
     }
 }
diff --git a/list/src/main/java/de/vivi/list/Main.java b/list/src/main/java/de/vivi/list/Main.java
index 3057002..3451e36 100644
--- a/list/src/main/java/de/vivi/list/Main.java
+++ b/list/src/main/java/de/vivi/list/Main.java
@@ -10,10 +10,10 @@ public class Main {
     public static void main(String[] args) {
         ByteList array = new ArrayByteList();
         ByteList linked = new LinkedByteList();
-//        ByteList combined = new CombinedByteList(16);
-//        testListVivi(array);
-        testListVivi(linked);
-//        testSortVivi(array);
+//        ByteList combined = new CombinedByteList(16); // Paul meinte das kann weg gelassen werden
+        testListVivi(array);
+        //testListVivi(linked);
+        testSortVivi(array);
         //testList(array);
 //        testList(linked);
 //        testList(combined);
@@ -31,9 +31,9 @@ public class Main {
         list.add((byte) 5);
         list.add((byte) -100);
 
-
-        System.out.println(list);
-        System.out.println(list.copy());
+//
+//        System.out.println(list);
+//        System.out.println(list.copy());
 //        list.remove(4);
 //        list.contains(5);
 //        System.out.println(list.contains(2));
@@ -156,12 +156,14 @@ public class Main {
 
     private static void testSortVivi(ByteList list) {
         ByteSort bubble = new BubbleSort();
-//        ByteSort merge = new MergeSort();
+        ByteSort merge = new MergeSort();
 //        ByteSort bogo = new BogoSort();
 
         // sort the lists with the sorting algorithm
 //        bubble.sort(list.copy());
-        System.out.println(bubble.sort(list.copy()));
+ //       System.out.println("bubblesort " + bubble.sort(list.copy()));
+        System.out.println();
+        System.out.println(merge.sort(list.copy()));
 //        merge.sort(list.copy());
 //        bogo.sort(list.copy());
     }
diff --git a/list/src/main/java/de/vivi/list/MergeSort.java b/list/src/main/java/de/vivi/list/MergeSort.java
new file mode 100644
index 0000000..f6a0343
--- /dev/null
+++ b/list/src/main/java/de/vivi/list/MergeSort.java
@@ -0,0 +1,53 @@
+package de.vivi.list;
+
+
+public class MergeSort implements ByteSort {
+    @Override
+    public ByteList sort(ByteList list) {
+        int mid = list.size() / 2;
+        ByteList leftList = createSubList(list, 0, mid);
+        ByteList rightList = createSubList(list, mid, list.size());
+
+        ByteList mergedList = mergeList(leftList, rightList, mid);
+        sortMergedList(mergedList);
+        return mergedList;
+    }
+
+    private void sortMergedList(ByteList mergedList) {
+        for (int i = 0; i < (mergedList.size() - 1); i++)
+            for (int j = 0; j < mergedList.size() - i - 1; j++)
+                if (mergedList.get(j) > mergedList.get(j + 1)) {
+                    byte temp = mergedList.get(j);
+                    mergedList.set(j, mergedList.get(j + 1));
+                    mergedList.set(j + 1, temp);
+                }
+    }
+
+    private ByteList mergeList(ByteList leftList, ByteList rightList, int mid) {
+        ByteList mergedList = new ArrayByteList();
+        for (int i = 0; i < mid; i++) {
+            mergedList.add(leftList.get(i));
+            mergedList.add(rightList.get(i));
+        }
+        return mergedList;
+    }
+
+    public ByteList createSubList(ByteList list, int start, int end) {
+        ByteList subList = new ArrayByteList();
+        for (int i = start; i < end; i++) {
+            subList.add(list.get(i));
+        }
+        return subList;
+    }
+
+    public ByteList sortSubList(ByteList list, int mid) {
+        for (int i = 0; i < mid - 1; i++)
+            for (int j = 0; j < mid - i - 1; j++)
+                if (list.get(j) > list.get(j + 1)) {
+                    byte temp = list.get(j);
+                    list.set(j, list.get(j + 1));
+                    list.set(j + 1, temp);
+                }
+        return list;
+    }
+}