#有点

woc = {"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"}
woc1 = ["reset", "board", "reboot", "backplane"]
woc2 = ["board", "add", "delete", "backplane", "abort"]

while True:
    try:
        w = input().split()
        if len(w) == 1:
            if w[0] in 'reset':
                print(woc['reset'])
            else:
                print("unknown command")
        else:
            b = []
            c = []
            for i in woc1:
                if w[0] == i[0:len(w[0])]:
                    b.append(i)
            for k in woc2:
                if w[1] in k[0:len(w[1])]:
                    c.append(k)
            if (len(b) != 0 and len(c) == 1) or (len(b) == 1 and len(c) != 0):
#                 print(b)
#                 print(c)
                for i in b:
                    for j in c:
                        if woc.get(i + ' ' + j):
                            print(woc.get(i + ' ' + j))
            else:
                print("unknown command")
    except:
        break