while 6:
a=raw_input();s=[];m='failed at: '
while a:
x=a[0];a=a[1:]
if x in'{[<(':s+=[x]
elif 0<ord(x)-ord(s[-1])<3:s.pop()
else:m+=x+a;s=a=0
print([]==s)*'yes'or m+'EOL'*(s>[])
Note that non-ascii characters in the above source code will be escaped (such as \x9f).