function BuildString(const ch: char; const len: byte): string;
var
  i: byte;
begin
  result := '';
  for i := 1 to len do
   result := ConCat(result, ch);
end;

procedure Triangle(const fileName: string);
var
  f: Text;
  ch: char;
begin
  assign(f, fileName);
  rewrite(f);

  for ch := 'a' to 'z' do
   writeln(f, BuildString(ch, 123 - ord(ch)));

  close(f);
end;

aaaaaaaaaaaaaaaaaaaaaaaaaa
bbbbbbbbbbbbbbbbbbbbbbbbb
cccccccccccccccccccccccc
ddddddddddddddddddddddd
eeeeeeeeeeeeeeeeeeeeee
fffffffffffffffffffff
gggggggggggggggggggg
hhhhhhhhhhhhhhhhhhh
iiiiiiiiiiiiiiiiii
jjjjjjjjjjjjjjjjj
kkkkkkkkkkkkkkkk
lllllllllllllll
mmmmmmmmmmmmmm
nnnnnnnnnnnnn
oooooooooooo
ppppppppppp
qqqqqqqqqq
rrrrrrrrr
ssssssss
ttttttt
uuuuuu
vvvvv
wwww
xxx
yy
z