见代码中注释

shu = 3200
user_shu = input('这台冰箱多少钱\n')
user_shu =int(user_shu)
while user_shu != shu:
    if user_shu > shu:
        user_shu = input('猜高了，再猜\n')
        user_shu = int(user_shu)
    if user_shu < shu:
        user_shu = input('猜低了，再猜\n')
        user_shu = int(user_shu)
print('恭喜你猜对了\n')


print(1+2)
print(2-1)
print(1-2)
print(1*2*3)
print(1/2)
print(1//2)#整除，向下取整
print(1%2)
print(1**2)#幂运算
print(2**2*4+6/2)#结合顺序一般和数学的一样，也可用小括号来提升优先级

shu1 = len('Hello World!')
shu2 = len("Hello world!")
print(shu1)
print(shu2)

python的空值为none，不能理解为0，0也是有意义的
布尔值和布尔代数的表示完全一致，一个布尔值只有True、False两种值布尔值 布尔值可以用and、or和not运算。
注意大小写！
True or False


number = 10
tt = 13
print(number+tt)
number += 199
print(number)


aa = 12.5
cc = 13
bb = int(aa)
dd = float(cc)
print(bb)
print(dd)
xx = bool(3)#bool除了0是false，其余值均返回ture
vv = bool(0)
print(xx)
print(vv)


list1 = [1,2,3,4,5,"a","b"]
list2 = ["d","f","c",'adfaef']
s1 = len(list2)
print(s1)
print(list1)
print(list2)
list2.append('ewjfgter')#往列表后面再加个元素
list2.pop()#默认就是最后一个元素,具体用法暂时还未学会
print(list2)


#tuple元组，和list列表有点像，但一旦初始化就不能再改变
#tuple元组使用（），而list使用[]
tuple1 = (1,2,3,4,5)
tuple2 = ("s","d",'fdsfg')
print(tuple1)
print(tuple2)


可变对象，不可变对象


a = 5
print(id(a))
a = 6
print(id(a))
print(a)
a=5
print(id(a))
#python 内置了字典：dict的支持，使用键值储存具有极快的查找速度

list列表使用[]
tuple元组，使用()
字典集合{}
python中是通过符号来区分吗？字典和集合又怎么区分


word = {'apple':'苹果','banana':'香蕉'}
scores = {'小张':100,'小李':80}
grad = {4:'很好',3:'好',2:'中',1:'差',0:'很差'}
print(word)
print(scores)
print(grad)
a = scores['小张']
b = grad[3]
print(a)
print(b)
#集合set


ch1 = input('输入灯的颜色')
if ch1 == '红灯':
    print('请你停车')
elif ch1 == '绿灯':
    print('快走')
else:
    print('冲过去')


score_chinese = 90
score_math = 70
score_english = 88
if score_english > 80 and score_math > 80 and score_chinese > 80:
    print('奖励你小红花')
else:
    print('小红花，想啥呢？')

a = int(input('请输入一个数'))
while a<10:
    print('还得加',a)
    a=a+1

import random
shu_tr = random.randint(1,99)  #生成1-99的一个随机数
shu_user = int(input('请在1-99之间猜数'))
while shu_user!=shu_tr:
    if shu_user>shu_tr:
        print('猜大了')
        shu_user = int(input('请再猜'))
    else:
        print('猜小了')
        shu_user = int(input('请再猜'))
print('猜对了，把你能的')


for i in  range(9):
    print(i+1)
range用法,一般与for搭配
从0生成9个数，0，1，2，3，4，5，6，7，8


fruits = ['banana','apple','mango']
for fruit in fruits:
    print('当前水果是',fruit)

##执行结果为
当前水果是 banana
当前水果是 apple
当前水果是 mango


打印1-10中的偶数
for i in range(10):
    num = i + 1
    if num % 2 == 0:
        print(num)
    else:
        continue
# 可以把continue删掉吗？
#不能


a = float(input())
b = '%.12f'%a
print(b)


a = 15e10
print(a)
b= int(a)
print(b)


a, b= map(int, input().split())#可以空格输入多个变量，相当于C里的scanf("%d%d",&a,&b);
print(a*b)


a, b= map(int, input().split())
c = a/b
d = a%b
print(int(c),int(d))


a, b, c = map(int, input().split())
print(int((a+b)/c))


a,b= map(int, input().split())
c = b/a
print('{:.3%}'.format(c))     #'{:.3%}'.format(c)为python的预格式化，3代表转换成百分数后小数位留3位


a = int(input())
if a%4==0:
    if a%100==0 and a%400!=0:
        print("N")
    else:
        print("Y")
else:
    print("N")


s = int(input())
t_wlak = s/1.2
t_bike = 27+23+s/3.0
if t_bike>t_wlak:
    print('Walk')
elif t_bike=0 and x<5:
    y = -x+2.5
elif x>=5 and x<10:
    y = 2-1.5*(x-3)*(x-3)
elif x>=10 and x<20:
    y = x/2-1.5
print('{:.3f}'.format(y))   #'{:.3}'.format(c)为python的预格式化，3代表小数位留3位

a = int(input())
i = 1
bb = 0
while i1000:
    chaoguo = a-1000
    cishu = int(chaoguo/500)+1
    qian = 8+cishu*4
    if b=='y':
        qian = qian + 5
    print(qian)

a = int(input())
b = a/100
b = int(b)
s = (a-(b*100))/10
s= int(s)
g = (a-(b*100))%10
g = int(g)
print('{}{}{}'.format(g,s,b))#占位符可以去掉空格


a1,a2,n = map(int,input().split())
d = a2-a1
# he = n*a1+(n*(n-1)*d)/2
an = a1+(n-1)*d
print(an)

通过列表做？尝试:失败
a1,a2,n = map(int,input().split())
d = a2-a1
list1 = [1,1]
i = 3
while i<=n:
    pp = i-1
    temp = int(list1[pp])+d
    list1.append(temp)
    i = i+1


n,k = map(int,input().split())
baifen = k/100
fangjia = 200
k = 0
# print(baifen)
i=1
while i<=20:
    qian = n*i
    if i>=2:
        fangjia = fangjia*(1+baifen)
    if qian>fangjia:
        k = 1
        m = i
        break
    i = i+1
if k==0:
    print('Impossible')
else:
    print(m)


斐波那契数列
k = int(input())
list1 = [1,1]
if k>=3:
    i = 3
    while i <= k:
        temp = list1[i - 3] + list1[i - 2]
        list1.append(temp)
        i = i + 1
    print(list1[k - 1])
else:
    print(1)


import math

v = int(input())
i = 1
while i<=v:#控制测试样例数
    n = int(input())
    x = n#从n开始增，找到最大公约数大于1的数
    while 1:
        list1 = list(str(x))
        chang = len(list1)
        pp = 1
        su_m = 0
        while pp<=chang:
            su_m = su_m+int(list1[pp-1])
            pp = pp+1
        # ii = su_m
        # while 1:
        #     if x%ii==0 and su_m%ii==0:
        #         break
        #     ii = ii-1
        ii = math.gcd(x,su_m)
        if ii>1:
            print(x)
            break
        else:
            x = x+1
    i = i+1


a = '这是个字符串'
print(isinstance(a,str))


assert 称为断言，当这个关键字后面的条件为假的时候，程序自动崩溃，并抛出AssertionError的异常
assert 3>4
可以用来运行那些必须得为真的程序


list1 = [213,'fdrs','svdfs32',423]
for i in list1:
    print(i)


for i in range(9):
    print(i)

for i in range(2,9):
    print(i)

for i in range(2,9,3):
    print(i)
print(list(range(2,9))

切片
a = str(input())
print(a[::-1])


n = int(input())
list1 = [1,1]
yyy = 0
if n>=3:
    i = 3
    while i <= n:
        temp = list1[i - 3] + list1[i - 2]
        list1.append(temp)
        i = i + 1
    yyy = list1[n - 1]
else:
    yyy = 1
result = yyy%10007
print(result)


字符串进阶
name = 'money'
print(name[0])
print(name[-4])
print(name[1:4:2])#切片[起始:结束:步长] 字符串[start: end: step] 这三个参数都有默认值，默认截取方向是从左往右的 start:默认值为0； end : 默认值未字符串结尾元素； step : 默认值为1；
#如果切片步长是负值，截取方向则是从右往左的，从左往右是0开始，从右往左是从-1开始计数
print(name[::-1])#从-1开始增加，有倒序输出的作用