Lesson 010: List: a hit array hormone

0. List can store some of what?

　　me: strings, numbers, lists, and so on and so forth.

　　Answer:

1. Which method add elements to the list there?

　　me：append()、extend()等

　　Reference answer: append (), extend () and insert ().

2.append () method and extend () methods are add elements to the end of the list, ask them what is the difference?

　　me：

In many cases both can be generic, but a big difference in processing time list elements:

Example:

>>> a = [1,2,3]; b=[4,5,6]

>>> a.append(b)

>>> a

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

>>> a.extend(b)

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

As can be seen from the above example obvious difference. That append can only add an element, and extend steps to add more elements, but a plurality of elements necessary

Shall be used [] enclosed. There is also an insert () method, can be inserted into specified positions in the list.

　　Answer:

　　　　append () method is used as a parameter to the end of the element added to the list.
　　　　extend () method as a parameter list sucked despreading end of the list.

Sample code:

>>> name = ['F', 'i', 's', 'h']
>>> name.append('C')
>>> name
['F', 'i', 's', 'h', 'C']
>>> name.extend(['.', 'c'])
>>> name
['F', 'i', 's', 'h', 'C', '.', 'c']
>>> name.append(['o', 'm'])
>>> name
['F', 'i', 's', 'h', 'C', '.', 'c', ['o', 'm']]

3. member.append ([ 'bamboo forest creek', 'Crazy obsession']) and member.extend ([ 'bamboo forest creek', 'Crazy obsession']) to achieve the same effect of it?

　　me: not the same, append () is added at the end of the list of elements, and extend () is a list of merger

4. A list name = [ 'F', 'i', 'h', 'C'], if you want to insert small turtle element 's' between the elements of 'i' and 'h', what methods should be used to insert?

　　me:name.insert（2，“s”）

Start work

　　me：

i=0
member = [ 'small turtle', 88 'night', 90, 'lost', 85, 'Yi Jing', 90 'Qiuwu sun', 88]
while 0 <= i <len(member):
	print(member[i])
	i+=1

　　Answer:

member = [ 'small turtle', 88 'night', 90, 'lost', 85, 'Yi Jing', 90 'Qiuwu sun', 88]
for each in member:
    print(each)

　　me：

i=0
member = [ 'small turtle', 88 'night', 90, 'lost', 85, 'Yi Jing', 90 'Qiuwu sun', 88]
while 0 <= i <len(member):
	if i % 2 !=0:
		print(member[i])
	else:
		print(member[i],end=" ")
	i+=1

member = [ 'small turtle', 88 'night', 90, 'lost', 85, 'Yi Jing', 90 'Qiuwu sun', 88]
for i in range(0,len(member)-1,2):
 	print(member[i : i+2])

　　Answer:

method one:
count = 0
length = len(member)
while count < length:
    print(member[count], member[count+1])
    count += 2

Method Two:    
    
for each in range(len(member)):
    if each%2 == 0:
        print(member[each], member[each+1])

Lesson 010: List: a hit array hormone

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