program p08;
uses Crt;
var  a,b,c,D:real;

begin
clrscr;
repeat
  write('Vloz parametr a : ');readln(a);
until (a<>0);
write('Vloz parametr b : ');readln(b);
write('Vloz parametr c : ');readln(c);
D:=b*b-4*a*c;
if D=0 then writeln('Rovnice ma jeden dvojnasobny koren ',-b/(2*a):5:3);
if D>0 then begin writeln('Rovnice ma tyto koreny :');
                  writeln((-b+sqrt(D))/(2*a):5:3);
                  writeln((-b-sqrt(D))/(2*a):5:3);
                  end;
if D<0 then begin writeln('Rovnice ma tyto komplexni koreny :');
                  writeln(-b/(2*a):5:3,'+',sqrt(-D)/(2*a):5:3,'i');
                  writeln(-b/(2*a):5:3,'-',sqrt(-D)/(2*a):5:3,'i');
                  end;
repeat until keypressed;
end.