def partition(arr, low, high):
pivot = arr[high]
i = low - 1
for j in range(low, high):
if arr[j] < pivot:
i += 1
arr[i], arr[j] = arr[j], arr[i]
arr[i + 1], arr[high] = arr[high], arr[i + 1]
return i + 1
def is_sorted(arr, low, high):
for i in range(low, high - 1):
if arr[i] > arr[i + 1]:
return False
return True
def quick_sort(arr, low, high):
if is_sorted(arr, low, high):
return
if low < high:
pi = partition(arr, low, high)
quick_sort(arr, low, pi - 1)
quick_sort(arr, pi + 1, high)
if __name__ == '__main__':
arr = [1, 2, 3, 4, 5]
n = len(arr)
quick_sort(arr, 0, n - 1)
print(arr)