Add mergeSort

Uebung 1/Algorithms.h

@@ -35,7 +35,7 @@ void insertionSort(Ware *waren[10], int sortby) {
   }
 }
 
-void quicksort(Ware *waren[10], int l, int u) {
+void quicksort(Ware *waren[], int l, int u) {
   int i = l, j = u;
   Ware *a;
   int pivot = waren[(l + u) / 2]->getSeriennummer();
@@ -61,3 +61,51 @@ void quicksort(Ware *waren[10], int l, int u) {
     quicksort(waren, i, u);
   }
 }
+
+void merge(Ware *array[], int left, int middle, int right) {
+  int n1 = middle - left + 1;
+  int n2 = right - middle;
+
+  Ware *leftArray[n1];
+  Ware *rightArray[n1];
+
+  for (int i = 0; i < n1; i++) {
+    leftArray[i] = array[left + i];
+  }
+  for (int j = 0; j < n2; j++) {
+    rightArray[j] = array[middle + j + 1];
+  }
+
+  int k = 0, l = 0, m = left;
+  while (k < n1 && l < n2) {
+    if (leftArray[k]->getBezeichnung() <= rightArray[l]->getBezeichnung()) {
+      array[m] = leftArray[k];
+      k++;
+    } else {
+      array[m] = rightArray[l];
+      l++;
+    }
+    m++;
+  }
+
+  while (k < n1) {
+    array[m] = leftArray[k];
+    k++;
+    m++;
+  }
+
+  while (l < n2) {
+    array[m] = rightArray[l];
+    l++;
+    m++;
+  }
+}
+
+void mergeSort(Ware *array[], int left, int right) {
+  if (left < right) {
+    int middle = left + (right - left) / 2;
+    mergeSort(array, left, middle);
+    mergeSort(array, middle + 1, right);
+    merge(array, left, middle, right);
+  }
+}

Uebung 1/Sortiment.cpp

@@ -20,6 +20,7 @@ void Sortiment::sort(int modus) {
     bubbleSort(this->waren);
     break;
   case 3:
+    mergeSort(this->waren, 0, 9);
     break;
   case 4:
     insertionSort(this->waren, 1);