How to find out two lists with same structure in python?

Question

Define a procedure, same_structure, that takes two inputs. It should output `True` if the lists have the same structure, and `False` otherwise. Two values, p and q have the same structure if: ``` Neither p or q is a list. Both p and q are lists, they have the same number of elements, and each element of p has the same structure as the corresponding element of q. ``` EDIT: To make the picture clear the following are the expected output ``` same_structure([1, 0, 1], [2, 1, 2]) ---> True same_structure([1, [0], 1], [2, 5, 3]) ---> False same_structure([1, [2, [3, [4, 5]]]], ['a', ['b', ['c', ['d', 'e']]]]) ---> True same_structure([1, [2, [3, [4, 5]]]], ['a', ['b', ['c', ['de']]]]) ---> False ``` I thought recursion would be best to solve this problem in python I have come up with the following code but its not working. ``` def is_list(p): return isinstance(p, list) def same_structure(a,b): if not is_list(a) and not is_list(b): return True elif is_list(a) and is_list(b): if len(a) == len…

Accepted Answer

Recursion would be a good idea, but not the way you've suggested it. First off (and this may be only a typo), you don't actually return anything here:

```
if len(a) == len(b):
    same_structure(a[1:],b[1:])
```

Second, you should recursively deal with each element, not each sublist. ie.:

```
if len(a) == len(b):
    for i in range(len(a)):
        if not same_structure(a[i], b[i]):
            return False
    return True
else:
    return False
```

Hope this helps.

How to find out two lists with same structure in python?

Solution

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