Hướng dẫn python enumerate offset

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Updated on Jan 07, 2020

The enumerate[] function takes an iterable and returns an enumerate object [an iterator] that produces a tuple of the form [index, value], where index refers to the offset of the item and item refers to the corresponding item from the iterable.

The syntax of enumerate[] function is as follows:

Syntax:

enumerate[iterable[, start=0]] -> iterator for index, value of iterable

Here is an example:

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>>> 
>>> list[enumerate["hello"]]
[[0, 'h'], [1, 'e'], [2, 'l'], [3, 'l'], [4, 'o']]
>>> 
>>>
>>> for index, value in enumerate["hello"]:
...     print[index, value]
... 
0 h
1 e
2 l
3 l
4 o
>>>

Try it out:

The following listing shows how enumerate[] works with a list, dictionary and tuple:

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>>> 
>>> for index, value in enumerate[[110, 45, 12, 891, "one"]]:
...     print[index, value]
... 
0 110
1 45
2 12
3 891
4 one
>>> 
>>> 
>>> for index, value in enumerate[{'name': 'Jane', 'age': 26, 'salary': 40000}]:
...     print[index, value]
... 
0 name
1 salary
2 age
>>> 
>>> 
>>> for index, value in enumerate[{1, 290, -88, 10}]:
...     print[index, value]
... 
0 -88
1 1
2 10
3 290
>>>

Try it out:

Setting the initial value of the index #

To set the initial value of the index, we use the start keyword argument.

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>>> 
>>> list[enumerate["hello", start=2]]
[[2, 'h'], [3, 'e'], [4, 'l'], [5, 'l'], [6, 'o']]
>>> 
>>>
>>> for index, value in enumerate["hello", start=2]:
... print[index, value]
... 
2 h
3 e
4 l
5 l
6 o
>>>

Try it out:

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