Implemented merge sort

merge_sort.c

@@ -3,11 +3,72 @@
  *-----------------------------------------------------------------------------
  * Exercise Number: S06
  * Title:			Insertion sort implementation
- * Author:			*/<your name>;/*
+ * Author:			Marc Tismonar
  *-----------------------------------------------------------------------------
  * Description:
  * Implements the merge sort strategy
  *-----------------------------------------------------------------------------
 */
 
-#include "merge_sort.h"
+#include "merge_sort.h"
+
+static void merge_sort_list_merge(IntList list, IntList left, IntList right, criterion_fn criterion) {
+    while (list_get_size(left) > 0 && list_get_size(right) > 0) {
+        if (criterion(list_get_at(left, 0), list_get_at(right, 0))) {
+            list_transfer_head(left, list);
+        } else {
+            list_transfer_head(right, list);
+        }
+    }
+    list_append(list, left);
+    list_append(list, right);
+}
+
+static IntList merge_sort_list_divide_merge(IntList list, IntList result, criterion_fn criterion) {
+    if (list_get_size(list) <= 1) {
+        list_append(result, list);
+        return result;
+    }
+
+    IntList left = list_obtain(), right = list_obtain();
+    IntList left_result = list_obtain(), right_result = list_obtain();
+
+    list_split(list, left, right, list_get_size(list) / 2);
+    merge_sort_list_divide_merge(left, left_result, criterion);
+    merge_sort_list_divide_merge(right, right_result, criterion);
+    merge_sort_list_merge(result, left_result, right_result, criterion);
+
+    list_release(&left);
+    list_release(&right);
+    list_release(&left_result);
+    list_release(&right_result);
+
+    return result;
+}
+
+/**
+ * Sorts the given list according to the merge sort strategy.
+ * 
+ * @param list The list to be sorted.
+ * @param criterion The pointer to the function that implements the sorting criterion.
+ * That function accepts two integer parameters and returns a boolean value.
+ */
+void merge_sort_list(IntList list, criterion_fn criterion) {
+    IntList result = list_obtain();
+    result = merge_sort_list_divide_merge(list, result, criterion);
+    list_clear(list);
+    list_append(list, result);
+    list_release(&result);
+}   
+
+/**
+ * Sorts the given array according to the merge sort strategy.
+ * 
+ * @param array The array to be sorted.
+ * @param length The length of the array.
+ * @param criterion The pointer to the function that implements the sorting criterion.
+ * That function accepts two integer parameters and returns a boolean value.
+ */
+void merge_sort_array(int array[], int length, criterion_fn criterion) {
+
+}

merge_sort.h

@@ -3,7 +3,7 @@
  * ---------------------------------------------------------
  * Exercise Number: S06
  * Title:			Insertion sort implementation
- * Author:			*/<your name>;/*
+ * Author:			Marc Tismonar
  * ----------------------------------------------------------
  * Description:
  * Implements the merge sort strategy
@@ -24,7 +24,7 @@
  * @param criterion The pointer to the function that implements the sorting criterion.
  * That function accepts two integer parameters and returns a boolean value.
  */
-void merge_sort_list(<params>);
+void merge_sort_list(IntList list, criterion_fn criterion);
 
 /**
  * Sorts the given array according to the merge sort strategy.
@@ -34,6 +34,6 @@ void merge_sort_list(<params>);
  * @param criterion The pointer to the function that implements the sorting criterion.
  * That function accepts two integer parameters and returns a boolean value.
  */
-void merge_sort_array(<params>);
+void merge_sort_array(int array[], int length, criterion_fn criterion);
 
 #endif