program Lab2_1;
uses crt;
const n = 6;
TextFile = 'file_in.pas';
type BTr = ^BTree;
     PTree = ^TTree;
     BTree = record
	data  : char;
	left  : PTree;
	right : PTree;
     end;

   TTree = object
   private
      barrier : boolean;
      zv : BTr;
      procedure CreateTree(fCh : char);
      function IsOper(C : char) : boolean;
      procedure KillSk(var S : string);
      function GetOperPos(S : string) : word;
   public
      constructor Create;
      procedure SetTree(S : string);
      function GetLevel : word;
      function GetValue : real;
      destructor Done;
   end;

var
   Tree : PTree;
   mL : integer;
   F : text;
   root : BTr;
   Str : string;
   level : word;

constructor TTree.Create;
begin
   barrier := true
end;

destructor TTree.Done;
begin
   if barrier then exit;
   zv^.left^.Done;
   zv^.right^.Done;
   dispose(zv^.left);
   dispose(zv^.right);
   dispose(zv)
end;

function Max(v1, v2 : word) : word;
begin
   if v1 > v2 then Max := v1 else Max := v2
end;

procedure ReadFile(var S : string);
var
   C : char;
begin
   S := '';
   reset(F);
   while not eof(F) do
   begin
      read(F, C);
      if C <> '=' then S := S + C
   end;
   close(F)
end;

procedure PrintTree(b : PTree; level : integer);
var i : integer;
begin
   if b^.barrier then exit;
   PrintTree(b^.zv^.right, level + 3);
   write('':level);
   writeln('':level,' ',b^.zv^.data);
   PrintTree(b^.zv^.left, level + 3)
end;

procedure TTree.CreateTree(fCh : char);
begin
   new(zv);
   new(zv^.left, Create);
   new(zv^.right, Create);
   zv^.data := fCh;
   barrier := false;
end;

function TTree.IsOper(C : char) : boolean;
begin
   if (C = '+') or (C = '-') or (C = '*') or (C = '/')
   then IsOper := true
   else IsOper := false
end;

procedure TTree.KillSk(var S : string);
var i, sk : integer;
begin
   while (S[1] = '(') and (S[length(S)] = ')') do
   begin
      sk := 0;
      for i := 2 to length(S)-1 do
      begin
	 if sk < 0 then exit;
	 if S[i] = '(' then inc(sk);
	 if S[i] = ')' then dec(sk)
      end;
      if sk = 0
      then S := copy(S, 2, length(S)-2)
      else
      begin
	 writeln (' Error! ');
	 ReadKey;
	 halt;
      end;
   end
end;

function TTree.GetOperPos(S : string) : word;
var i, sk, L : word;
begin
   sk := 0;
   L := length(S);
   for i := 1 to L do
   begin
      if S[i] = '(' then inc(sk);
      if S[i] = ')' then dec(sk);
      if (sk = 0) and IsOper(S[i]) then
      begin
	 GetOperPos := i;
	 exit
      end;
   end;
   GetOperPos := 0
end;

procedure TTree.SetTree(S : String);
var
   L, R : String;
   P, D  : word;
begin
   KillSk(S);
   D := length(S);
   P := GetOperPos(S);
   if P = 0
   then CreateTree(S[1]) else
   begin
      CreateTree(S[P]);
      L := copy(S, 1, P-1); KillSk(L);
      R := copy(S, P+1, D-P);	KillSk(R);
      zv^.left^.SetTree(L);
      zv^.right^.SetTree(R)
   end
end;

function TTree.GetLevel : word;
begin
   if barrier then GetLevel := 0
   else GetLevel := Max(zv^.left^.GetLevel + 1, zv^.right^.GetLevel + 1)
end;

function TTree.GetValue : real;
begin
   case zv^.data of
      '+'      : GetValue := zv^.left^.GetValue + zv^.right^.GetValue;
      '-'      : GetValue := zv^.left^.GetValue - zv^.right^.GetValue;
      '*'      : GetValue := zv^.left^.GetValue * zv^.right^.GetValue;
      '/'      : GetValue := zv^.left^.GetValue / zv^.right^.GetValue;
      '0'..'9' : GetValue := ord(zv^.data) - 48
   end
end;

procedure AssignFile;
begin
   assign(F, TextFile);
   {$I-} reset(F); {$I+}
   if IOResult <> 0 then
   begin
      writeln('Error: ', TextFile, ' Not Found ');
      readkey;
      halt
   end
end;

begin
   ClrScr;
   AssignFile;
   New(Tree, Create);
   ReadFile(Str);
   writeln(' Formula: ',str);
   Tree^.SetTree(Str);
   writeln(' Input Formula: ');
   if Tree^.barrier
   then writeLn(' Tree Is Empty ')
   else PrintTree(Tree, 0);
   level := Tree^.GetLevel-2;
   if level >= 0 then writeLn(' Level: ',level)
   else writeLn(' Error: level not found');
   writeLn(' Value: ',Tree^.GetValue:2:2);
   dispose(Tree, Done);
   ReadKey;
end.