7.逻辑运算 and or not

1）优先级 ()> not  > and > o r

and：真真为真，真假为假 ，假假为假

or：真真为真，真假为真，假假为假

print(2 > 1 and 1 < 4)  #and两边都为真，所以输出为真（）
print(2 > 1 and 1 < 4 or 2 < 3 and 9 > 6 or 2 < 4 and 3 < 2)
#先计算所有and，结果为真、假、假，or因为真假为真，所以输出为真

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

ps  int  ----> bool   非零转换成bool True   0 转换成bool 是False
2）x or y  如果x True，则返回x，如果x False，则返回y

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

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

　x and y  如果x Ture，则返回y，如果 x False，则返回x

print(1 and 2)  #2
print(0 and 2)  #0
print(2 or 1 < 3)  #2
print(3 > 1 or 2 and 2) #Ture