Sorry for asking here, since I can't find the information on usaco website.
Specifically, it's for this problem (http://www.usaco.org/index.php?page=viewproblem2&cpid=194#). My submission got accepted on usaco judge (https://ideone.com/dRl8T2) but fails on the following test cases
1 2 () Correct: 1 Mine: 0 1 6 ()(()) Correct: 4 Mine: 2
In general, my code should've failed on test cases where there exist concurrently balanced brackets starting at index 0.