Test Cases explained wrong?

for this test case
(((a+(b))+(c+d)))
The explanation is this : **
For the 1st test case: The subexpression “a+(b)” is surrounded by two pairs of brackets.**

But I cannot see that “a+(b)” is surrounded rather I think “((a+(b))+(c+d))” is sorrounded.

yes you are right

we will update it soon

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