python3 字符串 元组 列表 字典通用方法

运算符	描述	支持的容器类型
+	合并	字符串，列表，元组
*	复制	字符串，列表，元组
in	元素是否存在	字符串，列表，元组，字典
not in	元素是否不存在	字符串，列表，元组，字典

a = "Hello"
b = "world"
list1 = [10, 100]
list2 = [20, 100, 200]
dict1 = {"name": "小明"}
dict2 = {"name": "xiaoming", "age": 18}
tuple1 = (10, 20)
tuple2 = (10, 100)

# 合并操作
print(a + b)
print(list1 + list2)
print(tuple1 + tuple2)
'''
Helloworld
[10, 100, 20, 100, 200]
(10, 20, 10, 100)
'''

# 复制
print("hello " * 3)
print([10, 20] * 3)
print((10, 20) * 3)
'''
hello hello hello 
[10, 20, 10, 20, 10, 20]
(10, 20, 10, 20, 10, 20)
'''

print("a" in "abc")
print(10 in [10, 100])
print(10 in (10, 100))
print(10 in {"name": "xiaoming", "age": 10})
print("name" in {"name": "xiaoming", "age": 10})
'''
字典类型默认查找所有的key
True
True
True
False
True
'''

# len() 计算容器的个数
print(len("abc"))  # 3
print(len([1, 2]))  # 2
print(len((1, 2)))  # 2
print(len({"name": "xiaoming"}))  # 1
print(len({10, 100}))  # 2

# del 或 del() 删除
a = ""
del a  # 删除后无法继续使用

# max返回最大值
# min返回最小值
a = "abcde"
print(max(a))  # e
print(min(a))  # a
a = [10, 100, 1000]
print(max(a))   # 1000
print(min(a))  # 10

a = (10, 100, 1000)
print(max(a))  # 1000
print(min(a))  # 10

a = {"name": "xiaoming" , "age": 18}
print(max(a))  # name
print(min(a))  # age

# range
print("range-------------")
for i in range(1, 10, 2):
    print(i, end="")  # 13579
print()
for i in range(10):  # 只有一个值，表示结束位置，开始为0，步长为1
    print(i, end="")  # 0123456789
print()
print(type(range(10)))  # <class 'range'>

# enumerate(a, start=1) start省略默认为0
a = [1, 2, 3]
b = enumerate(a)  # <class 'enumerate'>
print(type(b))
for i in b:
    print(i, end="")  # (0, 1)(1, 2)(2, 3)
print()

# 类型转换
list1 = [1, 20, 30]
tuple1 = (1, 2, 3)
set1 = {10, 200, 1000}

# tuple
print(tuple(list1))  # (1, 20, 30)
print(tuple(set1))  # (200, 1000, 10)

# list
print(list(tuple1))  # [1, 2, 3]
print(list(set1))  # [200, 1000, 10]

# set
print(set(list1))  # {1, 20, 30}
print(set(tuple1))  # {1, 2, 3}