字符串的格式

 字符串的格式：

name = input("name:")

info = "xingming : %s"% (name)

print(info)

如果换行，则

name = input("name:")
age = input("age:")

info = '''xingming : %s
age: %s'''% (name,age)

print(info)

#%d=digit
#%f=float
#%s=string

数字类型

type(1)

type(1) is int

以下情况都是假

[]空列表

{}空字典

()空元组，空集合

‘’空字符串

0

&运算

|运算

60&13=12

 

异或运算：相同的是0，不同的是1，叫异或运算，60^13=49

 

按位取反

 

info= {}

info=info.fromkeys([1,2,3],{}) #初始化字典
print(info)

# 三级菜单

menu={
    "北京":{
        "海淀":{"五道口","亚运村","中关村",},
        "昌平":{"立水桥","霍营","温泉",},
        "朝阳":{"朝阳公园","团结湖","东四环",},
        "东城":{},
    },
    "上海":{},
    "山东":{},
}

exit_flag=False

while not exit_flag: #不为真
    for key in menu:
        print(key)

    choice = input(">:").strip()
    if len(choice) == 0:continue
    if choice == "q":
        exit_flag = True
        continue
    if choice in menu:    #省存在，进入下一级
        while not exit_flag:
            next_layer=menu[choice]
            for key2 in next_layer:
                print(key2)
            choice2 = input(">>:").strip()
            if choice2 == "b": break
            if len(choice2)== 0:continue
            if choice2 == "q":
                exit_flag = True
                continue
            if choice2 in next_layer:    #市存在，进入下一级
                while not exit_flag:
                    next_layer2=next_layer[choice2]
                    for key3 in next_layer2:
                        print(key3)
                    choice3 = input(">>>:").strip()
                    if choice3 == "b":break
                    if choice3 == "q":
                        exit_flag = True
                        continue


#切记写重复的代码，太低端，容易被开除

# 三元运算,不能带elif

a=3

b=5

c=a if a<b else b

print(c)



c=a if a<b and a==5 else b

print(c)



# 八进制,cot里面输入十进制的数字，得到8进制的结果

a=oct(8)

print(a)



# 16进制,hex里面输入十进制的数字，得到16进制的结果

b=hex(15)

print(b)

b=hex(186)

print(b)

# 16进制，0123456789ABCDEF

# 10=A

# 计算机底层用的都是16进制

# BH为后缀或者OX为前缀的数据，都是16进制的数据



# BF4.B5

# 1011 1111 0100 . 1011 0101





# 186

# 128 64 32 16 8 4 2 1

# 1   0   1  1 1 0 1 0

print(186-128-32)

ba