ユークリッドの互除法が読んでる本で出てきたので、軽く実装。
def euclid(a, b): numerator = max(a, b) denominator = min(a, b) if numerator == 0 or denominator == 0: return None times = numerator / denominator remainder = numerator - denominator * times if 0 < remainder: euclid(denominator, remainder) else: return denominator if '__main__' == __name__: print euclid(2340, 4)