1 +、* 操作适用于字符串、列表、元组（不适用于集合与字典）

str1 = "123456"
str2 = "789"
list1 = [1, 2, 3, 4, 5, 6]
list2 = [7, 8, 9]
tuple1 = (1, 2, 3, 4, 5, 6)
tuple2 = (7, 8, 9)
# 运算
str3 = str1 + str2
list3 = list1 + list2
tuple3 = tuple1 + tuple2
str4 = str1*2
list4 = list1*2
tuple4 = tuple1*2
# 输出
print(str3)
print(list3)
print(tuple3)
print(str4)
print(list4)
print(tuple4)

运行结果

123456789

[1, 2, 3, 4, 5, 6, 7, 8, 9]

(1, 2, 3, 4, 5, 6, 7, 8, 9)

123456123456

[1, 2, 3, 4, 5, 6, 1, 2, 3, 4, 5, 6]

(1, 2, 3, 4, 5, 6, 1, 2, 3, 4, 5, 6)

2 字符串、列表、元组的两种索引与切片（不适用于集合与字典）

第一种：从左往右，索引从0开始，依次增大1

第二种：从右往左，索引从-1开始，依次减小1

str1 = "123456"list1 = [1, 2, 3, 4, 5, 6]
tuple1 = (1, 2, 3, 4, 5, 6)
set1 = {1, 2, 3, 4, 5, 6}
# 切片
str2 = str1[1:3]
list2 = list1[1:3]
tuple2 = tuple1[1:3]
str3 = str1[-4:-2]
list3 = list1[-4:-2]
tuple3 = tuple1[-4:-2]
# 输出
print(str2)
print(list2)
print(tuple2)
print(str3)
print(list3)
print(tuple3)

运行结果

23

[2, 3]

(2, 3)

34

[3, 4]

(3, 4)

牛b11111111111111111111