Add bubble sort implementation in a.py

a.py

@@ -0,0 +1,55 @@
+def bubble_sort(arr):
+    """
+    冒泡排序算法
+    参数:
+        arr: 待排序的列表
+    返回:
+        排序后的列表
+    """
+    n = len(arr)
+    # 遍历所有数组元素
+    for i in range(n):
+        # 最后i个元素已经排好序
+        for j in range(0, n - i - 1):
+            # 如果当前元素大于下一个元素，则交换它们
+            if arr[j] > arr[j + 1]:
+                arr[j], arr[j + 1] = arr[j + 1], arr[j]
+    return arr
+
+
+def test_bubble_sort():
+    """测试冒泡排序算法"""
+    test_cases = [
+        ([], []),
+        ([1], [1]),
+        ([1, 2, 3], [1, 2, 3]),
+        ([3, 2, 1], [1, 2, 3]),
+        ([64, 34, 25, 12, 22, 11, 90], [11, 12, 22, 25, 34, 64, 90]),
+        ([5, 1, 4, 2, 8], [1, 2, 4, 5, 8]),
+        ([-5, -1, -4, -2, -8], [-8, -5, -4, -2, -1]),
+        ([0, 0, 0, 0], [0, 0, 0, 0]),
+        ([3.2, 1.5, 4.8, 2.1], [1.5, 2.1, 3.2, 4.8]),
+    ]
+
+    all_passed = True
+    for i, (input_arr, expected) in enumerate(test_cases):
+        # 复制输入数组，避免修改原数组影响后续测试
+        arr_copy = input_arr.copy()
+        result = bubble_sort(arr_copy)
+        if result == expected:
+            print(f"测试用例 {i + 1} 通过: {input_arr} -> {result}")
+        else:
+            print(f"测试用例 {i + 1} 失败: {input_arr} -> {result}, 期望: {expected}")
+            all_passed = False
+
+    if all_passed:
+        print("所有测试用例通过!")
+    else:
+        print("部分测试用例失败!")
+
+    return all_passed
+
+
+if __name__ == "__main__":
+    # 运行测试
+    test_bubble_sort()