(#2=dotimes(q 19)(#2#(p 19)(defun f(p q)(intern #1=(format()"~C~A"(code-char(+(if(> q 7)66 65)q))(1+ p))))(or(notany(defun g(r s)(find(f(+ p r)(+ q s))'#.(loop while(listen)collect(read))))'(0 0 -1 1)'(-1 1 0 0))(g 0 0)(write-line #1#))))
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