Merge pull request #380 from ruchikakengal/Add-Quick-sort

Add  Quick Sort Problem

Geeks For Geeks/Sorting problems/Quick sort.py

@@ -0,0 +1,53 @@
+
+def quick_sort(arr):
+    """
+    Main function to perform Quick Sort.
+    This function calls the helper function to sort the array using the divide-and-conquer strategy.
+    """
+    print(f"Initial Array: {arr}")
+    sorted_array = quick_sort_recursive(arr, 0, len(arr) - 1)
+    print(f"Sorted Array: {sorted_array}")
+    return sorted_array
+
+def quick_sort_recursive(arr, low, high):
+    """
+    Recursive helper function for Quick Sort.
+    It partitions the array into subarrays and sorts them recursively.
+    """
+    if low < high:
+        # Partition the array and get the pivot index
+        pivot_index = partition(arr, low, high)
+        print(f"Array after partitioning: {arr}, Pivot Index: {pivot_index}")
+
+        # Recursively sort elements before and after partition
+        quick_sort_recursive(arr, low, pivot_index - 1)
+        quick_sort_recursive(arr, pivot_index + 1, high)
+
+    return arr
+
+def partition(arr, low, high):
+    """
+    Partition the array around a pivot element.
+    Elements smaller than the pivot are moved to the left, and elements greater are moved to the right.
+    """
+    pivot = arr[high]  # Choose the last element as pivot
+    print(f"Using Pivot: {pivot} (from index {high})")
+    i = low - 1  # Pointer for the smaller element
+
+    # Traverse through the array and compare each element with the pivot
+    for j in range(low, high):
+        print(f"Comparing: {arr[j]} with Pivot: {pivot}")
+        if arr[j] <= pivot:
+            i += 1
+            arr[i], arr[j] = arr[j], arr[i]  # Swap
+            print(f"Swapped: {arr[i]} and {arr[j]}, Updated Array: {arr}")
+
+    # Place the pivot element in the correct position
+    arr[i + 1], arr[high] = arr[high], arr[i + 1]
+    print(f"Placing Pivot: {pivot} at correct position, Updated Array: {arr}")
+    return i + 1
+
+# Example Usage
+array = [10, 7, 8, 9, 1, 5]
+print("Quick Sort Example")
+quick_sort(array)