procedure Gnat.Spitbol.Patterns.E is A,B:Vstring:=V(Get_Line);begin
for I in 1..35 loop B:=B&Ascii.Lf&Get_Line;end loop;for I in S(b)'Range loop
if'e'=S(a)(1)Then Put(S(b)(abs((2*S(B)'Last+1)*(I/(S(B)'Last/2+2))-2*I+1)));else
Put(S(b)(abs((S(B)'Last+1)*(1-I Mod 2)-(I+1)/2)));end if;end loop;end;