#include <vcl.h>
#include <math.h>
#pragma hdrstop

#include "Unit1.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm1 *Form1;
//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
        : TForm(Owner)
{
}
//---------------------------------------------------------------------------

void __fastcall TForm1::Button1Click(TObject *Sender)
{
  double sum = 0, x, eps = 0.000001, temp;
  int i = 1, n = 1;
  double z = pow(-1, n), v = pow(x, 2 * n - 1)/(2 *n -1);
  String res = "fabs(x) > 1";
  x = StrToFloatDef(LabeledEdit1->Text, 0);
  if (fabs(x) <= 1)
  {
    temp = x;
    while (temp >= eps)
    {
      sum += temp;
      i++;
      if (i == 2)
      {
        n = 2;
        temp = x*x/2;
      }
      else
      {
        n += i;
        temp = z * v;
      }
    }
    res = sum;
  }
  Label1->Caption = res;
}
//---------------------------------------------------------------------------