Python怎么解包一个元组或列表_Python序列解包操作技巧

my_list = [1, 2, 3, 4, 5]
a = my_list[0]
b = my_list[1]
c = my_list[2]

my_list = [1, 2, 3, 4, 5]
a, b, c = my_list[:3]

*

my_list = [1, 2, 3, 4, 5]
a, b, *rest = my_list
print(a, b, rest)  # 输出: 1 2 [3, 4, 5]

*rest

my_list

rest

others

remaining

*

my_list = [1, 2, 3, 4, 5]
first, *middle, last = my_list
print(first, last, middle) # 输出: 1 5 [2, 3, 4]

def get_user_info():
    return "Alice", 30, "alice@example.com"

name, age, email = get_user_info()
print(name, age, email)  # 输出: Alice 30 alice@example.com

users = [("Alice", 30), ("Bob", 25), ("Charlie", 35)]
for name, age in users:
    print(f"{name} is {age} years old.")

a = 1
b = 2
a, b = b, a  # 交换 a 和 b 的值
print(a, b)  # 输出: 2 1

s = "hello"
a,b,c,d,e = s
print(a,b,c,d,e) # 输出：h e l l o

my_list = [1, 2, 3]
a, b = my_list  # 报错：ValueError: too many values to unpack (expected 2)

*

my_list = [1, 2]
a, b, c = my_list  # 报错：ValueError: not enough values to unpack (expected 3, got 2)

itertools.zip_longest

import itertools

my_list = [1, 2]
a, b, c = itertools.zip_longest(my_list, [None] * 3, fillvalue=None)
print(a, b, c) # 输出 1 2 None

my_list = [1, 2, 3, 4, 5]
sum_of_squares = sum(x * x for x in my_list)
print(sum_of_squares)  # 输出: 55

(x * x for x in my_list)

sum

points = [(1, 2), (3, 4), (5, 6)]
distances = [x * x + y * y for x, y in points]
print(distances)  # 输出: [5, 25, 61]

for x, y in points

x

y