#17 tre_quicksort

Author: wojtask

src/book/chapter7/problem5.py

@@ -0,0 +1,20 @@
+from book.chapter7.section1 import partition
+from book.data_structures import Array
+from book.data_structures import CT
+
+
+def tre_quicksort(A: Array[CT], p: int, r: int) -> None:
+    """Sorts an array using quicksort with tail-recursion elimination.
+
+    Implements:
+        TRE-Quicksort
+
+    Args:
+        A: an Array containing the values to be sorted
+        p: the lower index of the subarray to sort
+        r: the upper index of the subarray to sort
+    """
+    while p < r:
+        q = partition(A, p, r)
+        tre_quicksort(A, p, q - 1)
+        p = q + 1

test/test_book/test_chapter7.py

@@ -4,6 +4,7 @@
 from hypothesis.strategies import lists
 
 from book.chapter7.problem4 import stooge_sort
+from book.chapter7.problem5 import tre_quicksort
 from book.chapter7.section1 import quicksort
 from book.chapter7.section3 import randomized_quicksort
 from book.chapter7.section4 import insertion_quicksort
@@ -73,3 +74,14 @@ def test_stooge_sort(self, data):
 
         self.assertArraySorted(A, end=n)
         self.assertArrayPermuted(A, elements, end=n)
+
+    @given(st.data())
+    def test_tre_quicksort(self, data):
+        elements = data.draw(lists(integers(), min_size=1))
+        A = create_array(elements)
+        n = len(elements)
+
+        tre_quicksort(A, 1, n)
+
+        self.assertArraySorted(A, end=n)
+        self.assertArrayPermuted(A, elements, end=n)