10 acaccaaaca

Correct output: Yes

Your output: No

"Do stress testing to generate counter test case"

not sure if this helps but i stalled this problem thinking it was a lot of implementation as it allowed O(n^2) (i solved d before solving it), but it can be simply done in O(n) using a stack. my idea of it was that it has to be equal to a regular bracket sequence, so i just used a stack to check if it was equal to the topmost element in the stack, and if so i would remove the topmost element, and otherwise i would add the new element in. if its empty in the end it is valid. 364685342