Нужна помощь в разборе кода

[Raelag]

Здравствуйте!
Есть вот такой код длинного деления:

const
  Max = 255;
 
type
  Mas = Array[0..Max] Of Byte;
 
var
  S: Boolean;
  M1, M2: String;
  A1, A2, Mm1, Mm2, P: Mas;
  Cod: Integer;
  f, k, l, i, j, z, C, q, sum: Integer;
  M, N1, N2: Integer;
 
function Sravn(M: Integer; A1, Mm2: Mas): Boolean;
var
  k: Integer;
begin
  if M <> N2 then Sravn := (M > N2)
  else begin
    Sravn := true;
    k := 1;
    while (k <= M) and (A1[k] = Mm2[k]) do inc(k);
    if (k <= M) then Sravn := (A1[k] > Mm2[k]);
  end;
end;
 
begin
  WriteLn(' Vvedite delimoe');
  ReadLn(M1);
  N1 := LengTh(M1);
  for i := 1 To N1 Do Val(M1[i], Mm1[i], Cod);
  WriteLn(' Vvedite delitel');
  ReadLn(M2);
  N2 := LengTh(M2);
  for i := 1 To N2 Do Val(M2[i], Mm2[i], Cod);
  for i := 1 To N2 - 1 Do A1[i] := Mm1[i];
  M := N2 - 1;
  i := M;
  while(i < N1) Do
  begin
    while ((Sravn(M, A1, Mm2) = False) And (i < N1)) Do
    begin
      sum := 0;
      for q := 1 to M do
      begin
        sum := sum + A1[q];
        if sum <> 0 then break;
      end;
      if ((M > 0) and (sum <> 0)) or (M = 0) then M := M + 1;
      i := i + 1;
      A1[M] := Mm1[i];
    end;
    j := 0;
    while(Sravn (M, A1, Mm2) = True) Do
    begin
      f := N2 + 1;
      for k := M DownTo M - N2 Do
      begin
        f := f - 1;
        if A1[k] >= Mm2[f] Then A2[k] := A1[k] - Mm2[f]
              Else
        begin
          A1[k] := A1[k] + 10;
          A1[k - 1] := A1[k - 1] - 1;
          for l := k DownTo 1 Do
            if A1[l] < 0 Then
            begin
              A1[l - 1] := A1[l - 1] - 1;
              A1[l] := A1[l] + 10;
            end;
          A2[k] := A1[k] - Mm2[f];
        end;
      end;
      for l := M - N2 - 1 DownTo 1 Do
        A2[l] := A1[l];
      j := j + 1;
      P[i - N2 + 1] := j;
      while((A2 [1] = 0) And (M > 0)) Do
      begin
        for z := 1 To M - 1 Do
          A2[z] := A2[z + 1];
        M := M - 1;
        A2[M + 1] := 0;
      end;
      for z := 1 To M Do
        A1[z] := A2[z];
    end;
    while((A1 [1] = 0) And (M > 0)) Do
    begin
      for z := 1 To M - 1 Do
        A1[z] := A1[z + 1];
      M := M - 1;
      A1[M + 1] := 0;
    end;
  end;
  WriteLn(' Chastnoe: ');
  j := 1;
  while ((P[j] = 0) And (j >= N1 - N2)) Do j := j + 1;
  while P[j] = 0 do inc(j);
  for i := j To N1 - N2 + 1 Do Write(P[i]);
  WriteLn;
  if M = 0 Then
  begin
    M := 1;
    A1[M] := 0;
  end;
  WriteLn(' Ostatok');
  for i := 1 To M Do Write(A1[i]);
  ReadLn;
end.

Помогите, пожалуйста, с ним разобраться: что, как и для чего в нём предназначено (переменные, циклы).

И как, кстати, убрать из него вычисление остатка, если можно.

Заранее спасибо.