Рекурсия и дополнение программы

program Project1;
 
{$APPTYPE CONSOLE}
 
{$R *.res}
 
uses
  System.SysUtils;
 
type Queens = array[1..8] of integer;
 
var
  Qs: Queens;
 
function IsValid(r: Queens; step: integer) : boolean;
var i,j: integer;
begin
  IsValid:=true;
  if step<=1 then exit;
  for i:=1 to step-1 do
    for j:=i+1 to step do
     begin
       if (r[i]=r[j]) or (abs(r[i]-r[j])=abs(i-j)) then begin
         IsValid:=false;
         exit
       end;
     end;
end;
 
procedure WriteSolution;
var i,j: integer;
begin
  writeln('');
  for i:=1 to 8 do begin
    write('---[');
    for j:=1 to 8 do
      if qs[i]=j then write('♦') else begin
        if ((i xor j) and 1) = 1 then write('░') else write('▓');
      end;
    writeln(']---');
  end;
end;
 
procedure FindSolutions(n: integer);
var i: integer;
begin
  if n>8 then WriteSolution
  else for i:=1 to 8 do
    begin
      Qs[n]:=i;
      if IsValid(Qs,n) then FindSolutions(n+1);
      Qs[n]:=0;
    end;
end;
 
begin
  FindSolutions(1);
  Readln;
end.

function IsValid(r: Queens; step: integer) : boolean;
var i,j: integer;
begin
IsValid:=true;
if step<=1 then exit;
for i:=1 to step-1 do
for j:=i+1 to step do
begin
if (r[i]=r[j]) or (abs(r[i]-r[j])=abs(i-j)) then begin
IsValid:=false;
exit
end;
end;