¡Nuevo curso! ¡Todo programador debería aprender IA Generativa!
Prueba una lección gratuita0
List Function
Hello guys! can you explain me this function? i'm so confused with this output where item's list starts with 0 yes but when i put "len" method, output will be confusing coz it mixed with the start of '0' and starts with '1'. nums = [1, 2, 3, [1, 2, 3, [2,5,[3]]], 4, 5, 6, []] print(len(nums[3][3])) print(len(nums[3][3][2])) #output: 3 1
3 Respuestas
+ 4
First let me clarify what len is.
len means length.
print(len([1, 2, 3, 4]))
>> 4
And for your case, that is a nested list.
- - - - - - - - - - - -
( 1 )
print(len(nums[3][3]))
First we have to get first the element list of nums[3][3]
nums[3] = [1,2,3,[2,5,[3]]]
Now let's get the fourth element of nums[3]
nums[3][3] = [2, 5, [3]]
And the length of this list is 3:
First element: 2
Second element: 5
Third element: [3]
- - - - - - - - - - - -
( 2 )
For the second one, we just need to get the third element of our previous list which is nums[3][3].
nums[3][3] = [2, 5, [3] ]
nums[3][3][2] = [3]
The third element or nums[3][3][2] is [3].
Now the length of [3] is 1.
- - - - - - - - - - - - - - -
If my explanation is still unclear, please feel free to ask. Thanks!
+ 2
Nice! thank you so much for the very clear explanation!
i got it now it search for the final item in the list then measure what its length.thanks!
+ 1
I think you still need a little correction. It doesn't search anything and the final item is not important.
The numbers in 'nums[3][3]' are indices! They start counting at 0.
So we access nums,
get the element with index 3, which is
[1, 2, 3, [2,5,[3]]],
and of that list again get the element with index 3, which is the list [2,5,[3]].
The length of that list is 3.
In the next example we have a third index. So from the list [2,5,[3]] we get the element with index 2, which is [3], a list with 1 element.
Add more output to get a better understanding:
print(nums[3])
print(nums[3][3])
print(nums[3][3][2])