tests2: move into tests

1 files changed, 83 insertions, 0 deletions

diff --git a/tests/tests2/25_quicksort.c b/tests/tests2/25_quicksort.c
new file mode 100644
index 0000000..5cc08bd
--- /dev/null
+++ b/tests/tests2/25_quicksort.c
@@ -0,0 +1,83 @@
+#include <stdio.h>
+
+int array[16];
+
+//Swap integer values by array indexes
+void swap(int a, int b)
+{
+   int tmp  = array[a];
+   array[a] = array[b];
+   array[b] = tmp;
+}
+
+//Partition the array into two halves and return the
+//index about which the array is partitioned
+int partition(int left, int right)
+{
+   int pivotIndex = left;
+   int pivotValue = array[pivotIndex];
+   int index = left;
+   int i;
+
+   swap(pivotIndex, right);
+   for(i = left; i < right; i++)
+   {
+      if(array[i] < pivotValue)
+      {
+         swap(i, index);
+         index += 1;
+      }
+   }
+   swap(right, index);
+
+   return index;
+}
+
+//Quicksort the array
+void quicksort(int left, int right)
+{
+   if(left >= right)
+      return;
+
+   int index = partition(left, right);
+   quicksort(left, index - 1);
+   quicksort(index + 1, right);
+}
+
+int main()
+{
+   int i;
+
+   array[0] = 62;
+   array[1] = 83;
+   array[2] = 4;
+   array[3] = 89;
+   array[4] = 36;
+   array[5] = 21;
+   array[6] = 74;
+   array[7] = 37;
+   array[8] = 65;
+   array[9] = 33;
+   array[10] = 96;
+   array[11] = 38;
+   array[12] = 53;
+   array[13] = 16;
+   array[14] = 74;
+   array[15] = 55;
+
+   for (i = 0; i < 16; i++)
+      printf("%d ", array[i]);
+
+   printf("\n");
+
+   quicksort(0, 15);
+
+   for (i = 0; i < 16; i++)
+      printf("%d ", array[i]);
+
+   printf("\n");
+
+   return 0;
+}
+
+/* vim: set expandtab ts=4 sw=3 sts=3 tw=80 :*/