python学习第二天笔记四，随笔

#非空即真，非０即真
#实现同样的功能，代码越少越牛逼

#a=1
#b=2
#print(a==b)
#s=[1,2,3,4,5,6,]
#print(1 not in s)
a=[]
b=‘‘
c=()
if a:
    print(‘真 ‘)
else:
    print(‘假‘)
e=‘aa‘
if e:
        print(‘真 ‘)
else:
        print(‘假‘)
f=None
if f:
    print("真")
else:
    print(‘假‘)
#import this
#not 的意思是取反，假假即真

#a=[1,1,2,3,4,5,6,72]
#b=[1,1,2,3,4,5,6,72]
#b=a
#for i in b:
#    if i%2!=0:
#        a.remove(i)
 #   print(a)
 a1 = ‘niuhanyang‘
 b1 = a1
 print(id(a1))
 print(id(b1))
 a1=‘lololo‘
 print(id(a1))
 print(id(b1))
 #a = b = c = d =0
 #e,f ,g=1,2,3
 a,b=1,1
# c=a
# a=b
 #b=c
 b,a=a,b#python不需要引入第三方变量可以交换a和b的值
 #a = a+b
 #b = a-b
 #a = a-b #只限于int类型的
 

python学习第二天笔记四，随笔

原文：https://www.cnblogs.com/duxiansheng/p/9144188.html