梯形图输出A~Z

打印以下图形。
                         A
                        ABA
                       ABCBA
                      ABCDCBA
                     ABCDEDCBA
                    ABCDEFEDCBA
                   ABCDEFGFEDCBA
                  ABCDEFGHGFEDCBA
                 ABCDEFGHIHGFEDCBA
                ABCDEFGHIJIHGFEDCBA
               ABCDEFGHIJKJIHGFEDCBA
              ABCDEFGHIJKLKJIHGFEDCBA
             ABCDEFGHIJKLMLKJIHGFEDCBA
            ABCDEFGHIJKLMNMLKJIHGFEDCBA
           ABCDEFGHIJKLMNONMLKJIHGFEDCBA
          ABCDEFGHIJKLMNOPONMLKJIHGFEDCBA
         ABCDEFGHIJKLMNOPQPONMLKJIHGFEDCBA
        ABCDEFGHIJKLMNOPQRQPONMLKJIHGFEDCBA
       ABCDEFGHIJKLMNOPQRSRQPONMLKJIHGFEDCBA
      ABCDEFGHIJKLMNOPQRSTSRQPONMLKJIHGFEDCBA
     ABCDEFGHIJKLMNOPQRSTUTSRQPONMLKJIHGFEDCBA
    ABCDEFGHIJKLMNOPQRSTUVUTSRQPONMLKJIHGFEDCBA
   ABCDEFGHIJKLMNOPQRSTUVWVUTSRQPONMLKJIHGFEDCBA
  ABCDEFGHIJKLMNOPQRSTUVWXWVUTSRQPONMLKJIHGFEDCBA
 ABCDEFGHIJKLMNOPQRSTUVWXYXWVUTSRQPONMLKJIHGFEDCBA
ABCDEFGHIJKLMNOPQRSTUVWXYZYXWVUTSRQPONMLKJIHGFEDCBA

// 老师的程序

program exqj1_1;
var
      n, i, j : char;
     k : integer;
begin
      for n := 'A' to 'Z' do
      begin
        for k := 1 to 90-ord(n) do
            write(' ');
        for i := 'A' to n do
            write(i);
        for j := pred(n) downto 'A' do
            write(j);
        writeln;
      end;
      readln;
end.

// 我修改的程序

program exqj1_1;
var
        n : char;

function suc(b, e : char) : integer;
begin
     if (b < e) then
     begin
          write(b);
          suc(succ(b), e);
          write(b);
     end
     else
         write(b);
end;

begin
        for n := 'A' to 'Z' do
        begin
             write(' ' : ord('Z')-ord(n)+1);
             suc('A', n);
             writeln;
        end;
        readln;
end.

program exqj1_1;
var
     n : char;
     i : integer;
begin
      for n := 'A' to 'Z' do
      begin
        for i := 1 to ord('Z')-ord(n) do
            write(' ');
        for i := ord('A')-ord(n) to ord(n)-ord('A') do
             write(chr(ord(n)-abs(i)));
        writeln;
      end;
      readln;
end.