day2 python 语言元素

day2

语言元素

'''
使用input函数输入
使用int()进行类型转换
用占位符格式化输出的字符串
'''
a = int(input("a ="))//参数提醒用户输入格式
b = int(input("b= "))
print("%d +%d =%d"%(a,b,a+b))
print("%d //%d =%d"%(a,b,a//b))
print("%d+%d ="%(a,b,a/b))

-----------------------------------------------------
a =1234
b= 2345
1234 +2345 =3579

______________________________________
_______________________________________

使用type()检查变量的类型
"""
a=100
b=12.34
c=1+5j
d="hello,word"
e = True
print(type(a))
print(type(b))
print(type(c))
print(type(d))
print(type(e))

----------------------------------
<class 'int'>
<class 'float'>
<class 'complex'>
<class 'str'>
<class 'bool'>

---

"""
运算符
[] ,[:] 下标 切片
** 指数
~ 按位取反
>> ,<< 右移，左移
& 按位与
^ ,| 按位异或 按位或
is ,not is  身份运算符
in ,not in 成员运算符
not ,or, and 逻辑运算符
"""
a =5
b=10
c=3
d=4
e =5
a+=b
a-=c
a*=d
a/=e
print("a=",a)
flag1=3>2
flag2=2<1
flag3 =flag1 and flag2
flag4 =flag1 or flag2
flag5 = not flag1
print("flag1 =",flag1)
print("flag2 =",flag2)
print("flag3 =",flag3)
print("flag4 =",flag4)
print("flag4 =",flag5)
print(flag1 is True)
print(flag2 is not False)

---------------------------------------
a= 9.6
flag1 = True
flag2 = False
flag3 = False
flag4 = True
flag4 = False
True
False