Python 语法练习题

001、strings=["a","as","bat","car","dove","python"] 过滤掉长度小于等于2的字符串，并将剩下的字符串转换成大写字母形式。

方法一：

strings=["a","as","bat","car","dove","python"]

y = filter(lambda string: len(string) > 2, strings)
list(map(lambda s: s.upper(), y))

# [i.upper() for i in y]

方法二：

strings=["a","as","bat","car","dove","python"] 

[i.upper() for i in y]

 

002、 strings=["a","as","bat","car","dove","python"] 创建一个指向列表位置的映射关系的字典。

方法一：

strings=["a","as","bat","car","dove","python"]

dic = {}
for i in range(len(strings)):
    dic[i] = strings[i]

dic

方法二：

strings=["a","as","bat","car","dove","python"]

dic = {}
for i, s in enumerate(strings):
    dic[i] = s
    
dic

 

方法三：

strings=["a","as","bat","car","dove","python"]

dict((k, v) for k, v in enumerate(strings))

方法四：

strings=["a","as","bat","car","dove","python"]

{i: s for i, s in enumerate(strings)}

 

003、some_tuples=[(1,2,3),(4,5,6),(7,8,9)] 将这个整数元组构成的列表成为一个简单的整数列表。

方法一：

some_tuples=[(1,2,3),(4,5,6),(7,8,9)]

lst = []
for tup in some_tuples:
    for num in tup:
        lst.append(num)
        
lst

方法二：

some_tuples=[(1,2,3),(4,5,6),(7,8,9)]

[num for tup in some_tuples for num in tup ]

 

004、all_data=[["Tom","Billy","Jefferson","Andrew","Wesley","Steven","Joe"], ["Susie","Casey","Jill","Ana","Eva","Jennifer","Stephanie"]]我们要找出带有2个或以上的字母e的名字，并将它们放入一个新列表.

方法一：

all_data=[["Tom","Billy","Jefferson","Andrew","Wesley","Steven","Joe"],
          ["Susie","Casey","Jill","Ana","Eva","Jennifer","Stephanie"]]
[s for lst in all_data for s in lst if s.count('e') >= 2]