//Проверить, имеется ли в заданном тексте баланс открывающих и закрывающих скобок, имея в виду,
//что балансом, например, будет комбинация (…), в то время как комбинация )..(..)..( балансом не является.

program lab_9;
uses
   crt;

function CheckString (InputString: String): boolean;
var
   count: integer;
   currentPosition: integer;
   openBracket, closeBracket: integer;
begin
   openBracket:= 0;
   closeBracket:= 0;
   count:= 0;
   currentPosition:= 1;
   while (count >= 0) and (currentPosition <= length (InputString)) do
   begin
      if InputString[currentPosition]= '(' then
      begin
         inc (openBracket);
         inc (count);
      end;
      if InputString[currentPosition]= ')' then
      begin
         inc (closeBracket);
         dec (count);
      end;
      inc (CurrentPosition);
   end;
   if (openBracket = 0) then
      writeln ('In the text there is no opening brackets')
   else
      if (closeBracket = 0) then
         writeln ('In the text there is no closing brackets');

   if (count <> 0) then
      CheckString:= false
   else
      CheckString:= true;
end;

function InText: string;
var
   Fil: text;
   FString: string;
   adds: string;
begin
   writeln ('Enter the name file:');
   readln (adds);
   while not FileExists (adds) do
   begin
      writeln ('False name. Try again:');
      readln (adds);
   end;
   assign (Fil, adds);
   reset (Fil);
   while not Eof (Fil) do
   begin
      readln (Fil, Fstring);
      writeln (Fstring);
   end;
   close (Fil);
   Intext:= Fstring;
end;

var
   InString: String;
   choise: byte;
begin
   repeat
     writeln ('Input method: 1 - keyboard | 2 - text file');
     readln (choise);
     case choise of
        1:
           begin
              writeln ('Enter text string:');
              readln (InString);
           end;
        2: InString:= InText;
      end;
      if CheckString (InString) then
         writeln ('There is a balance brackets')
      else
         writeln ('There is no balance brackets');
         writeln ('To exit the program, press Esc, to repeat - any other key');
   until (readKey = #27);
end.