1 files changed, 88 insertions, 0 deletions

diff --git a/converter/quicksort.cpp b/converter/quicksort.cpp
new file mode 100644
index 000000000..9bc1d477f
--- /dev/null
+++ b/converter/quicksort.cpp
@@ -0,0 +1,88 @@
+#include "quicksort.h"
+
+
+
+
+// Quicksort controller function, it partitions the different pieces of our array.
+void quicksort(int *arIntegers, int left, int right)
+{
+/*    cout << "quicksort ([" << arIntegers[0] << ","
+                          << arIntegers[1] << ","
+                          << arIntegers[2] << ","
+                          << arIntegers[3] << ","
+                          << arIntegers[4] << ","
+                          << arIntegers[5] << ","
+                          << arIntegers[6] << "],"
+                          << left << ","
+                          << right << ")\n";
+*/
+    if (right > left)
+    {
+         int pivotIndex = median3(arIntegers,left,right);
+         int pivotNewIndex = partition(arIntegers, left, right, pivotIndex);
+
+         // Recursive call to quicksort to sort each half.
+         quicksort(arIntegers, left, pivotNewIndex-1);
+         quicksort(arIntegers, pivotNewIndex+1, right);
+    }
+}
+
+int median3(int *arIntegers,int left,int right)
+{
+        int center = (left+right)/2;
+
+   if(arIntegers[center] < arIntegers[left])
+        swap(arIntegers[left],arIntegers[center]);
+   if(arIntegers[right] < arIntegers[left])
+        swap(arIntegers[left],arIntegers[right]);
+   if(arIntegers[right] < arIntegers[center])
+        swap(arIntegers[center],arIntegers[right]);
+
+   swap(arIntegers[center],arIntegers[right-1]);
+
+   return center;
+}
+
+// This function takes an array (or one half an array) and sorts it.
+// It then returns a new pivot index number back to quicksort.
+int partition(int *arIntegers, int left, int right, int pivot)
+{
+/*     cout << "partition ("<< arIntegers[0] << ","
+                          << arIntegers[1] << ","
+                          << arIntegers[2] << ","
+                          << arIntegers[3] << ","
+                          << arIntegers[4] << ","
+                          << arIntegers[5] << ","
+                          << arIntegers[6] << "],"
+                          << left << ","
+                          << right << ")\n";
+*/
+     int pivotValue = arIntegers[pivot];
+
+     // Swap it out all the way to the end of the array
+     // So we know where it always is.
+     swap(arIntegers[pivot], arIntegers[right]);
+     int storeIndex = left;
+
+     // Move through the array from start to finish comparing each to our
+     // pivot value (not index, the value that was located at the pivot index)
+     for (int i = left; i < right; i++)
+     {
+         if (arIntegers[i] <= pivotValue)
+         {
+             swap(arIntegers[i], arIntegers[storeIndex]);
+             storeIndex++;
+         }
+     }
+     swap(arIntegers[storeIndex], arIntegers[right]);
+     return storeIndex;
+}
+
+// Simple swap function for our in place swapping.
+void swap(int &val1, int &val2)
+{
+    int temp = val1;
+    val1 = val2;
+    val2 = temp;
+}
+