python基础练习,循环、列表、字典、数组

# encoding: utf-8
'''
@author:    mark
@file:      20200214.py
@time:      2020/2/14 14:21
@software:  PyCharm
'''

'''
#初始学习python
print("hello word")     #打印hello word
price = 10   #初始化变量price
rating = 4.9     #初始化变量rating
name = "mark"   #初始化变量name
is_published = False    #初始化变量is_published
print(price)    #打印price
'''

'''
#控制台输入使用
name = input('what is your name? ')     #控制台输入值赋值给name
favorite_color = input("what is your favorite color ? ")    #控制台输入值赋值给favorite_color
print("Hi " + name + "your facorite_color  " + favorite_color)  #打印Hi name your facorite_color favorite_color
'''
'''
#控制台输入使用
birth_year = input("Birth year: ")  #控制台输入值赋值给birth_year
print(type(birth_year))     #打印控制台输入值的类型
age = 2020 - int(birth_year)    #根据控制台输入的值计算年龄
print(type(age))    #打印年龄的类型
print(age)  #打印年龄
'''

'''
#控制台输入使用,以及加减乘除运算
weight_lbs = input('Weight (lbs): ')    #控制台输入值赋值给weight_lbs
weight_kg = float(weight_lbs) * 0.45    #weight_lbs 转换为公斤
print(weight_kg)    #打印体重kg
weight_kg = input('Weight (kg): ')  #控制台输入体重kg
weight_lbs = float(weight_kg) / 0.45    #体重公斤转换为磅
print(weight_lbs)   #打印体重 磅

print(10 / 3)   #除法,带小数点
print(10 // 3)  #取商
print(10 % 3)   #取余
print(10 ** 3)  #次方
x = 10  #初始化X
x += 3  #X自加3 X = X + 3
print(x)    #打印X
x -= 3  #X自减3 X = X - 3
print(x)    #打印#
x = 10 + 3 ** 3 ** 2 # 同理 x = 3 ** (3 ** 2)
print(x)
'''

'''
#字符串的截取
course = "Python's Course for Beginners "   #初始化字符串
print(course)   #打印字符串
print(course[0])    #打印字符串第一个字符
print(course[0:3])  #打印字符串第一个到第四个字符
print(course[1:])   #打印从第二个字符开始的整个字符串
print(course[:5])   #打印开始的五个字符串
print(course[-2])   #打印倒数第二个字符
print(course[1:-1])     #打印第二个字符到倒数第二个字符
'''

'''
#f字符串使用,调用变量
first = 'John'  #初始化变量first
last = 'Smith'  #初始化变量last
message = first + ' [' + last + '] is a coder'  #字符串拼接
print(message)  #打印拼接的字符串
msg = f'{first} [{last}] is a coder'    #使用f字符串进行拼接字符串
print(msg)  #打印拼接的字符串
'''
'''
#字符串操作
course = 'Python for Beginners'     #初始化字符串
print(course.find('Beginners'))     #查找第一次出现Beginners时的脚标
print(course.replace('Beginners', 'Absoulte Beginners'))    #Absoulte Beginners替换字符串中的Beginners
print('Python' in course)   #查看Python是否在字符串中
print(len(course))  #查看字符串的长度
print(course.upper())   #字符串全部大写
print(course.lower())       #字符串全部小写
'''
'''
#math计算
import math #引入math
x = 2.9 #初始化X
print(round(x))     #四舍五入
print(abs(-x))      #绝对值
print(math.ceil(x))     #向上取整
print(math.floor(x))    #向下取整
'''

'''
#if语句
is_hot = True   #初始化is_hot
is_cold = True  #初始化is_cold
if is_hot :     #判断是否为真
    print("It's a hot day")     #打印It's a hot day
    print("Drink plenty of water")  #打印Drink plenty of water
elif is_cold:   #判断是否为真
    print(" It's a cold day")   #打印It's a cold day
    print("Wear warm clothes")  #打印Wear warm clothes
else:   #其他情况
    print("It's a lovely day")  #打印It's a lovely day
print(" Enjoy your day")    #打印Enjoy your day

price = 1000000     #初始化price
has_good_credit = True  #初始化has_good_credit

if has_good_credit:     #判断has_good_credit是否为真
    down_payment = 0.1 * price      #运算
else:   #其他情况
    down_payment = 0.2 * price      #运算
print(f"Down payment: ${down_payment}")    #打印 Down payment: $down_payment
'''

'''
#if语句以及逻辑连接
has_high_income = True  #初始化has_high_income
has_good_credit = True  #初始化has_good_credit
has_criminal_record = False #初始化has_criminal_record

if has_good_credit and has_high_income: #has_good_credit和has_high_income是否同时为真
    print("has_good_credit and has_high_income Eligible for loan")  #打印has_good_credit and has_high_income Eligible for loan
if has_good_credit or has_high_income:  #has_good_credit和has_high_income是否有一个为真
    print("has_good_credit or has_high_income Eligible for loan")   #打印has_good_credit or has_high_income Eligible for loan
if has_good_credit and not has_criminal_record: #has_good_credit为真且has_criminal_record为假
    print("Eligible for loan")  #打印Eligible for loan

temperature = 30    #初始化temperature
if temperature > 30:    #temperature > 30是否为真
    print("It's a hot day") #打印It's a hot day
else:   #其他
    print("It's not a hot day") #打印It's not a hot day

#名字长度判断
name = "John smith" #初始化name
if len(name) < 3:   #判断len(name) < 3是否为真 
    print("Name must be at least 3 characters.")    #打印
elif len(name) > 50:    #判断len(name) > 50是否为真
    print("Name must be a maximum of 50 characters.")   #打印
else:   #其他情况
    print("Name looks good!")   #打印

#体重转换
weight = int(input('Weight: ')) #对控制台输入的值进行类型转换
unit = input('(L)bs or (K)g: ') #控制台输入值赋值给unit
if unit.upper() == "L": #unit.upper() == "L"是否为真
    converted = weight * 0.45   #运算
    print(f"You are {converted} kilos") #打印You are converted kilos
else:   #其他情况
    converted = weight / 0.45   #运算
    print(f"You are {converted} kilos") #打印You are converted kilos
'''

'''  
#while循环语句
i = 1   #初始化i
while i <= 5:   #i <= 5是否为真
    print('*' * i)  #打印*
    i += 1  #自加
print("Done")   #打印Done

#猜数字
secret_number = 9   #初始化secret_number
guess_count = 0     #初始化guess_count
guess_limit = 3     #初始化guess_limit
while guess_count < guess_limit:    #guess_count < guess_limit是否为真
    guess = int(input('Guess: '))   #控制台输入赋值给guess
    guess_count += 1    #自加
    if guess == secret_number:  #guess == secret_number是否为真
        print('You win!')   #打印You win!
        break   #跳出循环
else:   #其他
     print('Sorry , you failed!')   #打印Sorry , you failed!
'''

'''
#while循环和if语句结合的案例
#开车,①quit为退出,help为帮助信息,start为开始,stop为结束,②且已经开启的不能再次开启
command = "" #初始化command用以判断是否跳出循环
started = False #初始化started,默认车是关闭状态,防止车被重复开启
while command.lower() != "quit":    #判断是否可以跳出循环
    command = input("> ").lower()   #控制台输入值赋给command
    if command.lower() == "help":   #判断是否需要帮助
        print('start/stop/quit')    #输出帮助信息
    elif command.lower() == 'start':    #判断是否为开车信息
        if started:     #车是否已经开启
            print("car is already start")   #打印car is already start
        else:   #车没有开启
            started = True  #变更车的状态信息
            print('Start the car')  #打印Start the car
    elif command.lower() == 'stop':     #判断是否为停车信息
        if not started:     #车是否已经停
            print("car is already stopped")     #打印car is already stopped
        else:       #车没有停
            started = False     #变更车的状态信息
            print('stop the car ')      #打印stop the car 
    elif command == "quit":     #判断是否为退出信息
        break       #跳出循环
    else:       #其他情况
        print("don't understand")      # 打印don't understand
'''

'''
#循环遍历
prices = [10, 20, 30]   #初始化prices
total = 0       #设定遍历的初始值
for price in prices:   #遍历的条件 
    total += price      #自加
print(f"Total:{total}") #输出遍历结果
'''

''' 
#所有坐标
for x in range(4):  #设置循环条件
    for y in range(3):      #设置二级循环条件
        print(f'({x},{y})')     #输出结果

numbers = [5, 3, 5, 3, 3]   #设置初始numbers
for x_count in numbers:     #设置循环条件
    # print('X' * x)
    output = ''     #输出值初始设置
    for count in range(x_count):       #设置输出值循环条件
        output += 'X'   #输出特征设置
    print(output)   #打印输出

#数组列表
names = ['John', 'Bob', 'Mosh', 'Sarah']    #设置初始列表names
print(names)    #打印输出列表
print(names[0])     #打印第一个元素
print(names[2:])    #打印第三个到最后一个元素
print(names)    


#查询列表中的最大值
numbers = [3, 6, 2, 8, 4, 10]      #设置初始列表numbers
max = numbers[0]       #设置最大值的初始值
for number in numbers:  #设置循环条件
    if number > max:    #进行判断是否为最大值
        max = number    #赋值
print(max)  #输出最大值
'''

'''  
#数组操作
matrix = [
    [1, 2, 3],
    [4, 5, 6],
    [7, 8, 9],
]       #初始化数组matrix
print(matrix[0][2])     #打印输出数组中第一个元素中的第三个元素
for row in matrix:      #设置循环列表中的第一层
    for low in row:     #设置循环列表中的第二层
        print(low)      #输出打印
'''

'''
#列表中的操作
numbers = [5, 2, 1, 5, 7, 4]   #初始化列表 numbers
print(numbers.sort())   #反向排序
numbers.reverse()   #按照从大到小排列
print(numbers)  #打印
numbers.append(14)  #列表中加入新的值
print(numbers)  #打印
numbers.insert(2, 100)  #在列表的第三个位置加入100
print(numbers)  #打印
numbers.remove(2)   #去除列表中的2
print(numbers)  #打印
numbers2 = numbers.copy()   #赋值
print(numbers2)     #打印
numbers.pop()   #去除末尾的值
print(numbers)  #打印
print(numbers.index(1))     #列表中的第二个值
print(numbers.count(5))    #列表中出现5的次数
numbers.clear()     #清除列表
print(numbers)      #打印

#清楚列表中的重复项
numbers = [5, 2, 3, 3, 2, 5, 23, 32]    #初始化列表numbers
for number in numbers:      #设置循环条件
    if numbers.count(number) != 1:     # 查询是否在列表里唯一
        numbers.remove(number)      #移除重复的元素
    # numbers.append(number)        #
print(numbers)      #打印没有重复值的列表

uniques = []    #设置一个空列表
for number in numbers:  #设置循环条件
    if number not in uniques:   #设置判断条件
        uniques.append(number)  #将符合条件的元素添加到空列表中
print(uniques)  #打印新的列表
'''


'''
#字典
customer = {
    "name": "John Smith",
    "age": 30,
    "is_verified": True
}       #初始化字典customer
customer["name"] = "Mark"   #更改对应key的value
print(customer["name"])     #打印对应key的value
print(customer["is_verified"])  #打印对应key的value
print(customer.get("name")) #打印对应key的value
'''

'''
#字典应用,输入数字对应英文
digits_mapping = {
    "1": "One",
    "2": "Two",
    "3": "Three",
    "4": "Four",
    "5": "Five",
    "6": "Six",
    "7": "Seven",
    "8": "Eight",
    "9": "Nine",
}   #初始化字典digits_mapping
phone = input("Phone: ")    #控制台输入
output = ''     #初始化输出
for ch in phone:    #设置循环条件
    output += digits_mapping.get(ch, "!") + " "     #获取对应字典中的value
print(output)   #打印
'''

 

posted @ 2020-02-22 18:06  MARK_REAPER  阅读(296)  评论(0编辑  收藏