B'You have given integers a , b , p , and q . Let f(x) = text{abs}( text{sin}( frac{p}{q} pi x)) . Find minimum possible integer x that maximizes f(x) where a <= x <= b . Each test contains multiple test cases. The first line contains the number of test cases t ( 1 <= t <= 100 ) -- the number of test cases. The first line of each test case contains four integers a , b , p , and q ( 0 <= a <= b <= 10^{9} , 1 <= p , q <= 10^{9} ). Print the minimum possible integer x for each test cases, separated by newline. In the first test case, f(0) = 0 , f(1) = f(2) approx 0.866 , f(3) = 0 . In the second test case, f(55) approx 0.999969 , which is the largest among all possible values. '...