打印以下图形4

      a
     bbb
    ccccc
   ddddddd
  eeeeeeeee
 f f f f f f f f f f f

program expicture4_1;
const lines = 6;
var
     i, j : integer;
     ch : char;
begin
        ch := 'a';
        for i := 1 to lines do
        begin
             write(' ' : lines-i+1);
             for j := 1 to 2*i-1 do
                 write(ch);
             writeln;
             ch := succ(ch);
        end;
        readln;
end.

program expicture4_2;
const b = 'a'; e = 'z';
var
     i : char;
     j : integer;
begin
        for i := b to e do
        begin
             write(' ' : ord(e)-ord(i)+1);
             for j := 1 to 2*(ord(i)-ord(b))+1 do
                 write(i);
             writeln;
        end;
        readln;
end.