while True:
try:
n=input().strip().split()
key=["reset","reset board","board add","board delete","reboot backplane","backplane abort"]
value=["reset what","board fault","where to add","no board at all","impossible","install first"]
if len(n) < 1 or len(n) > 2:
print("unknown command")
elif len(n) == 1:
if n[0] == key[0][0:len(n[0])]:
print(value[0])
else:
print("unknown command")
else:
b=[]
for i in range(1,len(key)):
a=key[i].split()
if n[0] == a[0][0:len(n[0])] and n[1] == a[1][0:len(n[1])]:
b.append(i)
if len(b) != 1:
print("unknown command")
else:
print(value[b[0]])
except:
break