SP68 EXPR1 - Expression

We are given an integer k and an arithmetic expression E with the operations '+', '-', and arguments from the set {0,1,...,9}. Is it possible to put some parentheses in E to get a new expression E' whose value equals k? If the answer is positive what is the minimum number of pairs of parentheses '(', ')' that are necessary?

The first line of the input file contains one positive integer d not larger than 10. This is the number of data sets. The data sets follow. Each set of data occupies two consecutive lines of the input file. The first line contains two integers n and k, 2

For each i = 1,...,d, your program should write to the i-th line of the output file one word 'NO' if the i-th input expression cannot be transformed into any expression of value k, and the smallest number of pairs of parentheses necessary otherwise.