Python pen question 1-21

1, how to achieve the Python list to the weight and maintain the original order

A: Then create a list, loop the original list element and determine if the current element is not in the new list, then add

2, there are now two tuples ((' A '), (' B ')), ((' C '), (' d ')), use the anonymous function in Python to generate the list [{' A ': ' B '},{' C ': ' d '}]

For:

#答案一test = Lambda T1,t2: [{i:j} for I,j in Zip (t1,t2)]print (Test (T1,T2)) #答案二print (list (map (lambda t:{t[0]:t[1]},zip (T1, T2))) #还可以这样写print ([{i:j} for I,j in Zip (t1,t2)]))

3, please give two points to find the Python sample code

For:

　　

def recursion_search (Data_source, find_n):
    MID = Len (data_source)//2
    If Len (data_source) >= 1:
        If Find_n > Data_source[mid]:
            Recursion_search (Data_source[mid + 1:], find_n)
        Elif Find_n < Data_source[mid]:
            Recursion_search (Data_source[:mid], find_n)
        Else
            Print (Data_source[mid])
    Else
        Print ("Not Found!")

4. The main difference between% and. format in Python string formatting

A: If you pass a number in%, you must specify the type, and format does not

5, *args,**kwargs Under what circumstances will be used, please example **kwargs application

A: *args,**kwargs is generally used for functions to pass multiple values,

**kwargs Example def x (**kwargs):

Return Kwargs

X (a=1)

6, x = ' foo '

y = 2

Print (X+y)

A.foo b.foo foo c.foo 2 D. An exception throw

7.

Kvps = {' 1 ': 1, ' 2 ': 2}
Thecopy = Kvps
kvps[' 1 '] = 5
sum = kvps[' 1 '] + thecopy[' 1 ']
Print (sum)

A.1  b.2     d.10

8, Sys.path.append ('/root/mods ')

A. Changing the python boot path b. Change Python's current working directory c. Add a new Python module search path d. Remove all folders from Mods

9.

Country_counter = {}

def addone (country):
    If country in Country_counter:
        Country_counter[country] + = 1
    Else
        Country_counter[country] = 1
AddOne (' China ')
AddOne (' Japan ')
AddOne (' China ')
a.0  B.1  c.2  D.3  e.4

10.

Names1 = [' Amir ', ' Barry ', ' chales ', ' Dao ']
Names2 = names1 #[' Alice ', ' Barry ', ' chales ', ' Dao ']
Names3 = names1[:]
Names2[0] = ' Alice '
NAMES3[1] = ' bob ' #[' Alice ', ' Bob ', ' chales ', ' Dao ']
sum = 0
For LS in (NAMES1,NAMES2,NAMES3):
    If ls[0] = = ' Alice ':
        sum + = 1
    If ls[1] = = ' Bob ':
        Sum + = 10
Print (sum)

b.12 c.21  d.22 e.33

11.

D = Lambda p:p*2
t = Lambda p:p*3
X= 2
x = d (x)
x = t (x)
x =d (x)
Print (x)
Answer: x = 24

12.

x = True
y = False
z = False
If x or Y and Z:
    Print (' Yes ')
Else
    Print (' No ')
Answer: Yes (and priority greater than or)

13.

How to implement Touple and list conversions in Python

Answer: touple (list)->touple list (touple)->list

14.

Please write a code implementation to delete the repeating element in a list

For:

NL = []
For I in L:
    If I in NL:
        Continue
    Nl.append (i)

15, how to get the list of the intersection and the difference set

Answer: LIST=L1&L2

List=l1-l2

16, the following code will output what

def ex (val,list=[]):
    List.append (Val)
    Return list
List1 = EX (10)
List2 = EX (123,[])
List3 = EX (' A ')
Print (LIST1,LIST2,LIST3)
Answer: [Ten, ' a '] [123] [Ten, ' a ']

17. How to write variable parameters and keyword parameters in Python

A: Variable parameters are written after the keyword parameter

18. What is a lambda expression

A: Alambda function is a function that can receive any number of arguments (including optional parameters) and return a single expression value

19. What is the difference between the match of RE and search?

A: Match will be matched from the beginning and will fail with a different head, search would match the full text

20, 1 or 2 and 1 and 2 output what, why

Answer: Output

And the expression is evaluated from left to right in the #python, and if all values are true, the last value is returned, and if there is a false, the first false value is returned

21, 1 < (2 = = 2) and 1 < 2 = = 2 Output What, why

Answer: Flase,true Reason

Python pen question 1-21