python实现基础排序算法

def bubble_sort(arr): """冒泡排序""" n = len(arr) for i in range(n): for j in range(0, n-i-1): if arr[j] > arr[j+1]: arr[j], arr[j+1] = arr[j+1], arr[j] return arr def selection_sort(arr): """选择排序""" n = len(arr) for i in range(n): min_idx = i for j in range(i+1, n): if arr[j] < arr[min_idx]: min_idx = j arr[i], arr[min_idx] = arr[min_idx], arr[i] return arr def insertion_sort(arr): """插入排序""" n = len(arr) for i in range(1, n): key = arr[i] j = i - 1 while j >= 0 and key < arr[j]: arr[j + 1] = arr[j] j -= 1 arr[j + 1] = key return arr def merge_sort(arr): """归并排序""" if len(arr) > 1: mid = len(arr) // 2 L = arr[:mid] R = arr[mid:] merge_sort(L) merge_sort(R) i = j = k = 0 while i < len(L) and j < len(R): if L[i] < R[j]: arr[k] = L[i] i += 1 else: arr[k] = R[j] j += 1 k += 1 while i < len(L): arr[k] = L[i] i += 1 k += 1 while j < len(R): arr[k] = R[j] j += 1 k += 1 return arr def quick_sort(arr): """快速排序""" if len(arr) <= 1: return arr pivot = arr[len(arr) // 2] left = [x for x in arr if x < pivot] middle = [x for x in arr if x == pivot] right = [x for x in arr if x > pivot] return quick_sort(left) + middle + quick_sort(right) # 测试排序算法 if __name__ == "__main__": test_array = [64, 34, 25, 12, 22, 11, 90] print("原始数组:", test_array) print("冒泡排序:", bubble_sort(test_array.copy())) print("选择排序:", selection_sort(test_array.copy())) print("插入排序:", insertion_sort(test_array.copy())) print("归并排序:", merge_sort(test_array.copy())) print("快速排序:", quick_sort(test_array.copy()))