Write a Python program to sum all the items in a list.Sample Solution : Python Code :view plaincopy to clipboardprint? def sum_list(items): sum_numbers = 0 for x in items: sum_numbers += x return sum_numbers print(sum_list([1,2,-8])) ...
print(list.clear()) #输出 None 1. 2. 3. 4. 反转(reverse) 排序(sort) 将用户输入的数从大到小排序,并输出 x=int(input("请输入x:")) y=int(input("请输入y:")) z=int(input("请输入z:")) list=[x,y,z] print(list) list.sort() list.reverse() for i in range(len(list)): pr...
Sale=collections.namedtuple('Sale','productid customerid data quantity price')sales=list()sales.append(Sale(432,921,"2018-04-01",3,8.2))sales.append(Sale(543,879,"2018-03-31",6,8.1))print(sales)[out][Sale(productid=432,customerid=921,data='2018-04-01',quantity=3,price=8.2),Sale(...
numbers = [value for value in range(3, 31) if value % 3 == 0] print("The first three items in the list are:" + numbers[:2]) print("Three items from the middle of the list are:" + numbers[1:3]) print("The last three items in the list are:" + numbers[-3:]) 1. 2. ...
for key, value in kwargs.items(): print(f"{key}: {value}") display_info(name="张三", age=30, occupation="软件工程师") 输出结果: name: 张三 age: 30 occupation: 软件工程师2.2 kwargs字典操作与解包 由于kwargs是一个标准的字典,你可以对其执行任何字典支持的操作,如查找、更新、删除等。此外...
# Creates a list of squares squares = [x**2 for x in range(10)] squares 通过添加条件来实现...
for cat in cats for dog in dogs for item in list_of_items 4.1.3 避免缩进错误 我们可以在for循环中执行更多操作,也可以在for循环结束后执行操作。 rapstars = ['XMASwu','bbnoS','Rich Brian'] for rapstar in rapstars: print(f"{rapstar},that was a great show!") print(f"I can't to ...
list2 = copy.deepcopy(list1) # 深拷贝 ```### 五、列表的性能优化 1. **选择合适的数据结构** - 如果需要频繁在头部插入或删除元素，考虑使用`collections.deque`。2. **避免不必要的复制** - 尽量使用切片或生成器表达式减少内存占用。3. **利用内置函数** - 如`sum()`、`max()`、`min()`...
defadd(a, b):returna + bsum= add(1,2,3)# >>> 执行结果如下# >>> sum = add(1, 2, 3)# >>> TypeError: add() takes 2 positional arguments but 3 were given AI代码助手复制代码 默认参数 在定义函数的时候,定义的参数含有默认值,通过赋值语句给参数一个默认的值。
fordogindogs:forcatincats:foriteminitem_list: 这些写法都是可以的。 在For循环中做更多操作 在for循环中,可以获取到每一个元素,可对每个元素执行任何操作。比如说我们对每一种蔬菜都输出一句话。 vegetables = ['potato','tomato','onion']fornameinvegetables:print(name +' is good !') ...