01 Python 逻辑运算

#基本运算符

#and or not

#优先级 （）>not>and>or

#and or not
print(2>1 and 1<4 or 2<3 and 9>6 or 2<4 and 3<2)
#         True     or    True    or     False
#True

print(3>4 or 4<3 and 1==1)                               #False
print(1<2 and 3<4 or 1>2)                                #True
print(2>1 and 3<4 or 4>5 and 2<1)                        #True
print(1>2 and 3<4 or 4>5 and 2>1 or 9<8)                 #False
print(1>1 and 3<4 or 4>5 and 2>1 and 9>8 or 7<6)         #False
print(not 2>1 and 3<4 or 4>5 and 2>1 and 9>8 or 7<6)     #False

数字与布尔值转换

#int-->bool
print(bool(2))   #True
print(bool(-2))  #True
print(bool(0))   #False
#bool-->int
print(int(True))   #1
print(int(False))  #0

x or y , x为真，值就是x，x为假，值是y

print(1 or 2)    #1
print(3 or 2)    #3
print(0 or 2)    #2
print(0 or 100)  #100

x and y, x为真，值是y,x为假，值是x

print(1 and 2)   #2
print(0 and 2)   #0

 in,not in :

判断子元素是否在原字符串（字典，列表，集合）中：

print('喜欢' in 'dkfljadklf喜欢hfjdkas')
print('a' in 'bcvd')
print('y' not in 'ofkjdslaf')

#and or 组合

print(2 or 100 or 3 or 4)  #2
print(0 or 4 and 3 or 2)   #3

#综合 第一个为布尔型则返回布尔型，第一个为数值型，则返回数值型

print(1>2 and 3 or 4 and 3<2) #False
print(2 or 1<3 and 2)         #2

print(0 or 5<4)               #False
print(0 and 3>1)              #0
print(3>1 and 0)              #0
print(3>1 and 2 or 2<3 and 3 and 4 or 3>2)  #2