运算和运算符
运算：一个或者一个以上的数据经过变化得到一个新值的过程。运算符：运算的符号就是运算符。
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| # + 加法运算符
result = 88 + 77
print(result)
# - 减法运算
result = 88 - 77
print(result)
# * 乘法运算符
result = 9 * 11
print(result)
# / 除法运算符(浮点类型)
result = 100 / 5
print(result)
# ** 幂运算
result = 5 ** 4#result = 5 * 5 * 5 * 5
print(result)
# // 地板除运算符
result = 47 // 10
print(result)
# % 取余运算符
result = 47 % 10
print(result)
#python 没有自增和自减运算符号
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| #1. > 大于运算符
result = 77 > 155
print(result)
#2. < 小于运算符
result = 14 < 19
print(result)
#3. >= 大于等于运算符
result = 15 >= 54
print(result)
#4. <= 小于等于运算
result = 45 <= 16
print(result)
#5. == 等于运算符 (六大类型不相同就不等于)
result = 55 == '55'
print(result)
#6. != 不等于运算符
result = 55 != 55
print(result)
#扩展：连续的比较运算
result = 44 < 55 < 33 # -> 44 < 55 并且 55 < 33
print(result)
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| #1.普通赋值运算
var = 250
print(var)
#2.加法赋值运算
var = 50
var += 10#var = var + 10
print(var)
#3.减法赋值运算
var = 100
var -= 88#var = var - 88
print(var)
#4.乘法赋值运算
var = 25
var *= 4#var = var * 4
print(var)
#5.除法赋值运算
var = 99
var /= 11#var = var / 11
print(var)
#6.取余赋值运算
var = 26
var %= 5#var = var % 5
print(var)
#7.取商赋值运算
var = 33
var //= 6#var = var // 6
print(var)
#8.幂赋值运算
var = 5
var **= 3#var = var ** 3
print(var)
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| #1.逻辑与运算（二目运算）-》有假则假
var1 = False
var2 = False
result = var1 and var2
print(result)
'''
True and True = True
False and True = False
True and False = False
False and False = False
'''
#2.逻辑或运算 -》 有真则真
var1 = False
var2 = False
result = var1 or var2
print(result)
'''
True or True = True
False or True = True
True or False = True
False or False = False
'''
#3.逻辑非运算（单目运算）-》真变假假变真
var = False
result = not var
print(result)
python不支持逻辑异或运算
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| #1，按位与运算
var1 = 25#11001
var2 = 12#01100
result = var1 & var2
print(result)
#2.按位或运算
var1 = 25
var2 = 12
result = var1 | var2
print(result)
#3.按位非运算
var = 8 #1000
result = ~var
print(result)
#4.按位异或运算
var1 = 25
var2 = 12
result = var1 ^ var2
print(result)
#5.左移运算 相当于乘以2的运算
var = 48
result = var << 2
print(result)
#6.右移运算 相当于地板除2
var = 36
result = var >> 3
print(result)
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| #id标识 系统为数据分配的编号
#is 检测是同一个
var1 = 'daxigua'
var2 = 'daxigua'
result = var1 is var2
print(result)
#查看id标识
print(id(var1),id(var2))
#注意：3.7以上版本 整数浮点数和字符串只要值一样，id标识就一样
#is not 检测是否不是同一个
var1 = 99
var2 = 98
result = var1 is not var2
print(result)
#查看id标识
print(id(var1),id(var2))
#其他数据类型 列表，元组，字典，集合 数据相同，id标识也不同
var1 = [1,2,3]
var2 = [1,2,3]
result = var1 is var2
print(result)
#查看id标识
print(id(var1),id(var2))
#连续赋值的列表，元组，字典集合id标识相同
var1 = var2 = [2,3]
result = var1 is var2
print(result)
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| #成员检测运算
#in 检测是否存在于容器中
#列表
#IT = ['PHP','JAVA','PYTHON','C++','C#','C']
#元组
#IT = ('PHP','JAVA','PYTHON','C++','C#','C')
#集合
#IT = {'PHP','JAVA','PYTHON','C++','C#','C'}
#字符串
#IT = 'PHPJAVAPYTHONC++C#C'
#字典（字典的成员运算仅仅进行键的检测）
IT = {'a':'PHP','b':'JAVA','c':'PYTHON','d':'C++','e':'C#','f':'C'}
result = 'a' in IT
print(result)
#not in 检测是否不再容器当中
IT = {'PHP','JAVA','PYTHON','C++','C#','C'}
result = 'lua' not in IT
print(result)
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