Brackets

A valid parentheses sequence is a non-empty string where each character is either '(' or ')', which satisfies the following constraint: You can find a way to repeat erasing adjacent pairs of parentheses '()' until it becomes empty. For example, '(())' and '()((()()))' are valid parentheses sequences, but ')()(' and '(()' are not. Mike has a valid parentheses sequence. He really likes everything