user_input = input() 
while user_input != 'end': 
    try: 
        #Possible ValueError 
        divisor = int(user_input)
        #Possible ZeroDivisionError 
        print(60 // divisor) #Truncates to an integer 
    except ValueError: 
        print('v')
    except ZeroDivisionError: 
        print('z')
    user_input = input() 
print('OK')