var a,b,c,x,x1,x2,D:real;
begin
writeln('Vitejte v programu na vypocet korenu kvadratickych rovnic.');
writeln('----------------------------------------------------------');
writeln('-----Program ukoncite zadanim 3 nulovych hodnot-----------');
writeln('zadej hodnoty:');
read(a,b,c);
while (a<>0) or (b<>0) or (c<>0) do
 begin
 if a=0 then if b<>0 then begin x:=-c/b;
                       writeln('liearni rovnice: x=',x);
                          end
                     else
                       writeln('nema reseni')
        else
          begin
          D:=b*b-4*a*c;
          if D=0 then begin
                            x:=-b/(2*a);
                            writeln('x=',x:5:1);
                            end
                       else
                       if D>0 then begin
                                 x1:=(-b-sqrt(D))/(2*a);
                                 x2:=(-b+sqrt(D))/(2*a);
                                 writeln('x1=',x1:5:1, ' x2=',x2:5:1);
                                 end
                             else
                             begin
                   writeln('x1=',(-b/(2*a)):5:1,'-i',(sqrt(-D)/(2*a)):5:1);
                   writeln('x2=',(-b/(2*a)):5:1,'+i',sqrt((-D)/(2*a)):5:1);
                             end;
        end;

      read(a,b,c);
      end;

end.