Create dual_pivot_quick_sort.py

Author: aniket05singh

sorts/dual_pivot_quick_sort.py

@@ -0,0 +1,56 @@
+class DualPivotQuickSort:
+    def sort(self, array):
+        if len(array) <= 1:
+            return array
+
+        self.dual_pivot_quick_sort(array, 0, len(array) - 1)
+        return array
+
+    def dual_pivot_quick_sort(self, array, left, right):
+        if left < right:
+            pivots = self.partition(array, left, right)
+
+            self.dual_pivot_quick_sort(array, left, pivots[0] - 1)
+            self.dual_pivot_quick_sort(array, pivots[0] + 1, pivots[1] - 1)
+            self.dual_pivot_quick_sort(array, pivots[1] + 1, right)
+
+    def partition(self, array, left, right):
+        if array[left] > array[right]:
+            array[left], array[right] = array[right], array[left]
+
+        pivot1 = array[left]
+        pivot2 = array[right]
+
+        pivot1_end = left + 1
+        low = left + 1
+        high = right - 1
+
+        while low <= high:
+            if array[low] < pivot1:
+                array[low], array[pivot1_end] = array[pivot1_end], array[low]
+                pivot1_end += 1
+            elif array[low] >= pivot2:
+                while low < high and array[high] > pivot2:
+                    high -= 1
+                array[low], array[high] = array[high], array[low]
+                high -= 1
+
+                if array[low] < pivot1:
+                    array[low], array[pivot1_end] = array[pivot1_end], array[low]
+                    pivot1_end += 1
+            low += 1
+
+        pivot1_end -= 1
+        high += 1
+
+        array[left], array[pivot1_end] = array[pivot1_end], array[left]
+        array[right], array[high] = array[high], array[right]
+
+        return low, high
+
+# Example usage
+if __name__ == "__main__":
+    sorter = DualPivotQuickSort()
+    sample_array = [3, 7, 8, 5, 2, 1, 9, 5, 4]
+    sorted_array = sorter.sort(sample_array)
+    print("Sorted array:", sorted_array)