8.5: Splitting/Joining Strings
- Page ID
- 117575
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- Use the
split()
method to split a string into substrings. - Combine objects in a list into a string using
join()
method.
split()
A string in Python can be broken into substrings given a delimiter. A delimiter is also referred to as a separator. The split() method, when applied to a string, splits the string into substrings by using the given argument as a delimiter. Ex: "1-2".split('-')
returns a list of substrings ["1", "2"]
. When no arguments are given to the split()
method, blank space characters are used as delimiters. Ex: "1\t2\n3 4".split()
returns ["1", "2", "3", "4"]
.
["1", "2', "3"]
[1, 2, 3]
join()
The join() method is the inverse of the split()
method: a list of string values are concatenated together to form one output string. When joining string elements in the list, the delimiter is added in-between elements. Ex: ','.join(["this", "is", "great"])
returns "this,is,great"
.
['A, beautiful, day, for, learning']
'A,beautiful,day,for,learning'
Write a program that accepts a comma-separated sequence of words as input, and prints words in separate lines. Ex: Given the string "happy,smiling,face"
, the output would be:
happy smiling face
Use the join()
method to repeat back a user's order at a restaurant, separated by commas. The user will input each food item on a separate line. When finished ordering, the user will enter a blank line. The output depends on how many items the user orders:
- If the user inputs nothing, the program outputs:
You ordered nothing
. - If the user inputs one item (Ex: eggs), the program outputs:
You ordered eggs
. - If the user inputs two items (Ex: eggs, ham), the program outputs:
You ordered eggs and ham
. - If the user inputs three or more items (Ex: eggs, ham, toast), the program outputs:
You ordered eggs, ham, and toast
.
In the general case with three or more items, each item should be separated by a comma and a space. The word "and" should be added before the last item.