Алгоритм сложения суммы "столбиком"

const
  maxL = 255;
  z = Ord('0');
var
  a, b, c : array [0..maxL] of Char;
  i : Integer;
begin
  a[0] := #0; for i := 1 to maxL do a[i] := '0';
  b[0] := #0; for i := 1 to maxL do b[i] := '0';
  c[0] := #0; for i := 1 to maxL do c[i] := '0';
 
  a[0] := Chr(10); a[1] := '9'; a[2] := '8'; a[3] := '7'; a[4] := '6'; a[5] := '5'; a[6] := '4'; a[7] := '5'; a[8] := '6'; a[9] := '7'; a[10] := '8';
  b[0] := Chr(10); b[1] := '8'; b[2] := '9'; b[3] := '8'; b[4] := '9'; b[5] := '8'; b[6] := '9'; b[7] := '8'; b[8] := '9'; b[9] := '8'; b[10] := '9';
 
  for i := 0 to Ord(a[0]) do c[i] := a[i];
  for i := 1 to Ord(b[1]) do c[i] := Chr(Ord(c[i]) + Ord(b[i])-z);
  if a[0] > b[0] then c[0] := a[0] else c[0] := b[0];
  for i := 1 to Ord(c[0]) do if c[i] > '9' then begin c[i+1] := Succ(c[i+1]); c[i] := Chr(Ord(c[i]) - 10); end;
  if c[Ord(c[0])+1] > '0' then c[0] := Succ(c[0]);
  
  for i := Ord(a[0]) downto 1 do Write(a[i]); Write('+'); for i := Ord(b[0]) downto 1 do Write(b[i]); Write('='); for i := Ord(c[0]) downto 1 do Write(c[i]); WriteLn;
end.