name = 'mkbk'  # 字符串变量
print(f"hello {name}")  # 输出 f 字符串

print("Python Rust")
print()
print("Python\tRust")  # 使用制表符
print()
print("Python\nRust")  # 使用换行符

# 在一行给多个变量赋值
msg1, msg2 = 'hello world', ' mkbk'
print(f"{msg1.title()}\n{msg1.upper()}")
print(f"{msg2}\n{msg2.strip()}")
print("file.txt".removesuffix(".txt"))

print(1, 1_000_000, 1.5)
print(True, False)  # 布尔值
print(1+1, 1.0+1.0, 1+1.0)
# 乘方、除法、整除法(向下取整)和求模
print(3**2, 3/2, 3//2, 5%2)

bikes = ['trek', 'redline', 'giant']
print(bikes)
print(bikes[0])  # 索引从0开始，第一个元素的索引是0
print(bikes[2], bikes[-1])

bikes = ['trek']
bikes[0] = 'giant'
print(bikes)

bikes = []
bikes.append('redline')
bikes.insert(0, 'trek')
print(bikes)

bikes = ['giant', 'trek', 'redline']
bikes.pop(0)  # 移除'giant'元素
print(bikes.pop())  # 移除'redline'元素并输出
print(bikes)

bikes = ['giant', 'trek', 'redline']
del bikes[0]  # 移除'giant'元素
bikes.remove('trek')  # 移除'trek'元素
print(bikes)

nums = [9, 6, 1, 4, 2]
print(len(nums))
print(sorted(nums))
print(nums)  # 原列表不变
# 列表排序(默认正序)
nums.sort()
print(nums)
# 列表排序(指定倒序)
nums.sort(reverse=True)
print(nums)
nums.reverse()  # 翻转列表
print(nums)

bikes = ['trek', 'redline']
for bike in bikes:
    print(bike.title())

print(range(2))
print(list(range(2)))

squares = []
for value in range(2, 5):
    squares.append(value**2)

squares_comp = [value**2 for value in range(2, 5)]
print(squares == squares_comp)  # 推导式会创建相同的元素
print(squares)
print(min(squares), max(squares), sum(squares))

bikes = ['trek', 'redline', 'giant']
print(bikes[1:])
print(bikes[:-1])
print(bikes[0:1])

bikes_copy = bikes[:]  # 对副本进行浅拷贝操作，这里不影响原列表
bikes_copy.reverse()
print(bikes)
print(bikes_copy)

dimensions = (200, 50)
for value in dimensions:
    print(value)

# 元组无法修改，但变量可以被重新赋值
dimensions = (300, 100)
print(dimensions)
dimensions = 100
print(dimensions)

condition1 = (100 == 100)  # True
condition2 = (100 != 100)  # False
condition3 = (100 < 200)  # True
condition4 = (100 >= 200)  # False
condition5 = ('a' in ['a'])  # True
condition6 = ('a' not in ['a'])  # False
condition7 = condition1 or condition2  # True
condition8 = condition1 and condition2  # False

age, vip = 12, False

if 0 <= age < 4 and vip:
    ticket_price =0
elif age < 18:
    ticket price =25
elif age < 65:
    ticket_price = 40
else:
    ticket_price =20

print(f'Ticket price is {ticket_price}.')

alien = {'color': 'green', 'points': 5}
print(alien['color'], alien.get('color'))

alien = {'color': 'green', 'points': 5}
alien['color'] = 'red'
alien['position'] = (0, 25)

print(alien)

d = {'a':1, 'b':2, 'c':3}
del d['a']
print(d.pop('c'))
print(d)

favorites = {'jen': 'python', 'edward': 'rust'}
print(len(favorites))
for name, language in favorites.items():
    print(f"{name} loves {language}.")

print(list(favorites.keys()))
print(list(favorites.values()))

squares = {x: x**2 for x in range(4)}  # 键是从0到3的整数，值是键的平方
keys, vals = [0, 1, 2, 3], [0, 1, 4, 9]
squares_zip = {key: val for key, val in zip(keys, vals)}

print(squares == squares_zip, squares)

name = input("Please enter your name: ")
print(f"Hello, {name}!")

age = input("How old are you? ")
print(type(age), type(int(age)))

pi = input("\nWhat's the value of pi? ")
print(type(pi), type(float(pi)))

current_number = 0
while True:
    current_number += 1
    if current_number > 5:
        break
    if current_number % 2 == 0:
        continue
    print(current_number)

def describe_pet(animal, name, color='yellow'):  # 形参color有默认值
    """显示宠物的信息"""
    print(f"My {animal}'s {name}, color is {color}.")


describe_pet('dog', 'Buddy')  # 位置实参
describe_pet(name='willie', color='black', animal='dog')  # 关键字实参

def add_if_same_or_sub(x, y):
    if x == y:
        return x + y
    return x - y

val1 = add_if_same_or_sub(5, 2)
val2 = add_if_same_or_sub(2, 2)
print(val1, val2)

def func(*args, **kwargs):
    print(f"args: {args}\nkwargs: {kwargs}")

func(1, 2, k='v')

class Car:
    def __init__(self, model, energy_capacity=100):
        """初始化类的属性"""
        self.model = model
        self.energy_capacity = energy_capacity

    def show_dashboard(self):
        print(f"Energy remain: {self.energy_capacity}%")

    def drive(self, distance_km):
        # 修改类的属性
        self.energy_capacity -= distance_km // 5

    def recharge(self) :
        # 修改类的属性
        self.energy_capacity = 100

class ElectricCar(Car):
    def __init__(self, model):
        """初始化子类的属性，子类继承了父类的方法和属性，
        我们可以调用父类的初始化方法来初始化父类的属性"""
        super().__init__(model)
        self.battery_status = 'safe'

    def check_battery_safe(self):
        print(f"Battery is {self.battery_status}!")


mycar = ElectricCar('Tesla-ModelX')
mycar.drive(50), mycar.show_dashboard()
mycar.check_battery_safe()
mycar.recharge(), mycar.show_dashboard()

from pathlib import Path

path = Path('msg.txt')
path.write_text('Hello mkbk!\nHappy coding!')

contents = path.read_text()
print(len(contents.splitlines()))
print(contents)

try:
    num = int(input("Type a number: "))
    answer = 5 + num
except ValueError:
    print("You must type a number!")
else:
    print(answer)
finally:  # 无论try块是否引发错误，都始终执行finally块
    print("Exit.")

import json

numbers = [2, 3, 5, 7, 11, 13]
contents = json.dumps(numbers)
numbers_load = json.loads(contents)
print(contents, numbers_load == numbers)