dsa

program Project4;

uses
   Math, System.SysUtils;

var
   Xpresent: Double;
   Xpast: Double;
   X: Double;
   EPS: Double;
   Product: Double;
   IsCorrect: Boolean;
   i: Integer;

Begin
   repeat
      Writeln(' Enter X ( -1 < X <= 1) ');
      IsCorrect := True;
      try
         Readln(X);
         if (X <= -1) or (X > 1) then
         begin
            IsCorrect := False;
            Writeln('Incorrect X. Try again');
         end;
      except
         Writeln('Input a number!');
         IsCorrect := False;

      end
   until IsCorrect;
   repeat
      Writeln(' Enter EPS(0 < EPS < 1)');
      IsCorrect := True;
      try
         Readln(EPS);
         if (EPS >= 1) or (EPS <= 0) then
         begin
            IsCorrect := False;
            Writeln('Incorrect EPS. Try again');
         end;
      except
         Writeln('Input a number!');
         IsCorrect := False;

      end
   until IsCorrect;
   Product := X;
   Xpast := X;
   Xpresent := -X * X;
   i := 2;
   while (abs(Xpresent / i - Xpast / (i - 1)) >= EPS) do
   begin
      Product := Product + Xpresent / i;
      Xpast := Xpresent;
      Xpresent := Xpresent * -X;
      i := i + 1;
   end;
   Writeln(' LN(1 + X) = ', Product:4:5);
   Writeln(' N = ', (i - 1));
   Readln;

end.