def query(x): print('?', '{0:.10f}'.format(x),flush=True) s = input() if s == '-1': raise Exception return True if s == 'Yes' else False import random def solve(): upper = 12.22 * pow(10, 74) lower = 0 for i in range(24): now = random.randint(lower, upper) if query(now): upper = now else: lower = now print('!', '{0:.10f}'.format(upper),flush=True) t = int(input()) for _ in range(t): solve()