python比较运算符
python比较运算符
# 比较运算符,比较运算符的结果为bool类型 a, b = 10, 20 print('a>b吗?', a > b) # False print('a<b吗?', a < b) # True print('a<=b吗?', a <= b) # True print(' a>-b吗?', a >= b) # False print(' a==b吗?', a == b) # False print('a!=b吗?', a != b) # True
"""一个 =称为赋值运算符,==称为比较运算符', 一个变最由三部分组成,标识,类型,值 ==比较是值还是标识? 是值。 比较标识是 is """
1 a = 10 2 b = 10 3 print(a == b) # value-> True 4 print(a is b) # id -> True地址相同 5 print(id(a), id(b)) # 17442692240 17442692240 6 lst1 = [11, 22, 33, 44] 7 lst2 = [11, 22, 33, 44] 8 print(lst1 == lst2) # value -->True 9 print(lst1 is lst2) # id -->False 10 print(id(lst1)) 11 print(id(lst2)) 12 print(a is not b) # False a的id与b的id是不相等的 13 print(lst1 is not lst2) # Ture a的id与b的id是不相等的