Dynamic nested brackets
We consider the problem of maintaining a string of n brackets '('or')' under the operation reverse(i) that changes the ith bracket from '('to')' or vice versa, and returns 'yes' if and only if the resulting string is properly balanced. We show that this problem can be solved on the RAM in time O(log n/log log n) per operation using linear space and preprocessing. Moreover, we show that this is opt