SP61 BRCKTS - Brackets

We will call a **bracket word** any word constructed out of two sorts of characters: the opening bracket "(" and the closing bracket ")". Among these words we will distinguish **correct bracket expressions**. These are such bracket words in which the brackets can be matched into pairs such that - every pair consists of an opening bracket and a closing bracket appearing further in the bracket word - for every pair the part of the word between the brackets of this pair has equal number of opening and closing brackets On a bracket word one can do the following operations: - **replacement** -- changes the i-th bracket into the opposite one - **check** -- if the word is a correct bracket expression ### Task Write a program which - reads (from standard input) the bracket word and the sequence of operations performed, - for every check operation determines if the current bracket word is a correct bracket expression, - writes out the outcome (to standard output).

Ten test cases (given one under another, you have to process all!). Each of the test cases is a series of lines. The first line of a test consists of a single number _n (1

For every test case your program should print a line: Test i: where i is replaced by the number of the test and in the following lines, for every check operation in the i-th test your program should print a line with the word YES, if the current bracket word is a correct bracket expression, and a line with a word NO otherwise. (There should be as many lines as check operations in the test.)