DateTime StartMoment = new DateTime();
DateTime EndMoment = new DateTime();
DateTime StartDate = new DateTime(txtStartDate.Value.Year, txtStartDate.Value.Month, txtStartDate.Value.Day);
DateTime CurrentDate = new DateTime(txtStartDate.Value.Year, txtStartDate.Value.Month, txtStartDate.Value.Day);
            
StartMoment = DateTime.Now;
int Age1=0;
for (int i = 0; i <= txtIteration.Value; i++)
{
   Age1 = (((CurrentDate.Year - StartDate.Year) * 365 - 
                 StartDate.Month * 30 - StartDate.Day + 
                 CurrentDate.Month * 30 + CurrentDate.Day) / 365);
                CurrentDate = CurrentDate.AddDays(1);
}
EndMoment = DateTime.Now;
TimeSpan Span = EndMoment - StartMoment;

lstResult.Items.Add("начальная дата - " + StartDate.ToLongDateString());
lstResult.Items.Add("начало         - " + StartMoment.ToLongTimeString());
lstResult.Items.Add("конечная дата  - " + CurrentDate.ToLongDateString());
lstResult.Items.Add("окончание      - " + EndMoment.ToLongTimeString());
lstResult.Items.Add("возраст        - " + Age1.ToString());
lstResult.Items.Add("время          - " + Span.TotalSeconds.ToString());

Calendar brDate = jDateChooser1.getCalendar();
Calendar currentDate=Calendar.getInstance();
long numberItem = Integer.parseInt(jTextField1.getText());
int age = 0;
Calendar startDate = Calendar.getInstance();
for (int i = 0; i < numberItem; i++) {
 int brYear = brDate.get(Calendar.YEAR);
 int currentYear = currentDate.get(Calendar.YEAR);
 int brMonth = brDate.get(Calendar.MONTH);
 int currentMonth = currentDate.get(Calendar.MONTH);
 int brDay = brDate.get(Calendar.DATE);
 int currentDay = currentDate.get(Calendar.DATE);
 age = ((currentYear-brYear)*10000 +
          (currentMonth-brMonth)*100 +
 (currentDay-brDay))/10000;
 // увеличиваем число на один день
 currentDate.add(Calendar.DATE,1);
}
Calendar endDate  = Calendar.getInstance();
long timeTest = endDate.getTimeInMillis()-startDate.getTimeInMillis();
DateFormat dateFormat = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss");
jTextArea1.append("Дата рождения: " + dateFormat.format(brDate.getTime())+"\n");
jTextArea1.append("Возраст:"+String.valueOf(age)+"\n");
jTextArea1.append("Дата окончания цикла:"+dateFormat.format(currentDate.getTime())+"\n");
jTextArea1.append("время теста:"+String.valueOf(timeTest)+" миллисек\n");

  DateTime Start = new DateTime();
  DateTime End = new DateTime();
  Start = DateTime.Now;
  int UpperBound = 200000000;
  bool[] PrimeNumbers = new bool[UpperBound];
  for (int i = 2; (i * i) < UpperBound; i++)
  {
     if (!PrimeNumbers[i])
       for (int j = (i * i); j < UpperBound; j += i)
         PrimeNumbers[j] = true;
  }
  End = DateTime.Now;
  Console.WriteLine("Calculation time is {0}s", (End-Start).TotalSeconds);
  Console.WriteLine("Press Enter to continue ...");
  Console.Read();

int N = 20000000;
boolean[] isPrime = new boolean[N] ;
Arrays.fill(isPrime, true);
isPrime[1] = false;
for (int i = 2; i * i < N; i++) {
  if (isPrime) {
    for (int j = i * i; j < N; j += i) {
      isPrime[j] = false;
    }
  }

  int UpperBound = 200000000;

int N = 20000000;

C# if (!PrimeNumbers[i])
Java  if (isPrime)

  int UpperBound = 200000000;

int N = 20000000;

if (isPrime)

if (isPrime != null)

for ( int k = 0; k < 20; k++ )
{
    Stopwatch stopWatch = new Stopwatch();
    stopWatch.Start();

    int upperBound = 20000000;
    bool[] primeNumbers = new bool[ upperBound ];

    for ( int i = 2; ( i * i ) < upperBound; i++ )
    {
        if ( !primeNumbers[ i ] )
            for ( int j = ( i * i ); j < upperBound; j += i )
                primeNumbers[ j ] = true;
    }

    stopWatch.Stop();

    Console.WriteLine( "Calculation time is {0}s", stopWatch.Elapsed.TotalSeconds );
}
Console.WriteLine( "Press Enter to continue ..." );
Console.Read();