#print
If a file name is given with the "ls" command,
it tells you whether that file exists.
The file name is listed if the file exists;
if it doesn't, a complaint is typed.
For example,
  ls george
will type "george" if the file exists,
and "george not found" if it is missing.

Is there a file named "alexander" in the
current directory?  Find out, then type "yes" or "no".
#copyin
#user
#uncopyin
#match no
#log
#next
4.2b 10