Python运算符

#Python算数运算符
a = 10; b = 20; c = "str"
print(a + b)
print(a - b)
print(a / b) #不会像java一样取整, 这样算起来很棒
print(a // b)#取整的除法, 和java一样
print(b % a)
print(a ** 2)#返回a的平方, 确实很方便
#print(a + c)#事实证明字符串不能和数字相加

#Python比较运算符
d = 10; e = "str"
print(d == a)
print(d != b)
print(d > b)
print(d >= a)
print(d <= a)
print(e == c) #字符串相等比较内容
#print(e > d) #不同的基本数据类型不能比较

#Python赋值运算符
a = 25
b += a; print(b) #等价于b = b + a
a -= 1; print(a)
a *= 2; print(a)
a /= 2; print(a)
a %= 2; print(a)
a **= 2; print(a)
a //= 1; print(a)

#Python位运算符
a = 60
b = 13
print(a & b)#按位与
print(a | b)#按位或
print(a ^ b)#按位异或
print(~a) #按位取反

#Python逻辑运算符
a = 10
b = -20   #非0代表true
c = 0     #0代表false
d = 'str' #非空代表true
e = ''    #空代表false
if(a and d):
    print("a 和 b 都是true")
else:
    print("a 或 b 是false")
if(a or e):
    print("a 或 e 是true")
if(not e):
    print("e 是false")

#Python成员运算符
a = 10
b = 20
list = [1, 10, 2, 3, 4]
if(a in list):
    print("a in list")
if('asd' not in  list):
    print("'asd' not in list")


#Python身份运算符
# is (is not)用来判断引用地址是否相同(是否指向同一内存区域)
a = 'aaa'
b = 'aaa'
c = 11
d = 11
print(a is b)
print(d is c)
print(b is not c)