while True:

try:
    
    str_input = input()
    order_dict = {
        'reset': 'reset what',
        'reset board': 'board fault',
        'board add': 'where to add',
        'board delete': 'no board at all',
        'reboot backplane': 'impossible',
        'backplane abort': 'install first',
    }
    others = 'unknown command'
    
    n = len(str_input.split())
        
    if n == 1:
        if 'reset'.startswith(str_input):
            print('reset what')
        else:
            print(others)
    elif n == 2:
        times = 0
        index = 0
        str1, str2 = str_input.split()
        for i in range(1, len(order_dict.keys())):
            order1, order2 = list(order_dict.keys())[i].split()
            if order1.startswith(str1) and order2.startswith(str2):
                times += 1
                index = i
        if times == 1:
            print(order_dict[list(order_dict.keys())[index]])
        else:
            print(others)
    else:
        print(others)
    
except:
    break