def gcd_main(): engine.start(games.gcd)
def main(): engine.start(calc)
def main(): start(calc)
def main(): start(even)
def main(): engine.start(gcd)
def calc_main(): engine.start(games.calc)
def main(): engine.start(even)
def main(): engine.start(prime)
def progression_main(): engine.start(games.progression)
def main(): start(prime)
def prime_main(): engine.start(games.prime)
def main(): engine.start(progression)
def main(): start(progression)
def questions_main(): engine.start(games.even)