C#

int year = 2009;
int month = 2;
int nos = 0;
DateTime startDate = new DateTime(year, month, 1);
DateTime endDate = startDate.AddMonths(1);
while (startDate.DayOfWeek != DayOfWeek.Monday)
    startDate = startDate.AddDays(1);
for (DateTime result = startDate; result < endDate; result = result.AddDays(7))
    nos+=1;

//Print nos.

int CountDaysInMonth(int month, int year, DayOfWeek dayToCount)
{
  DateTime dt = new DateTime(year, month, 1);
  int result = 0;
  for(int i = 0; i < DateTime.DaysInMonth(year, month); i++)
  {
    if(dt.DayOfWeek == dayToCount)
      result++;
    dt.AddDays(1);
  }
  return result;
}

int CountDaysInMonth(int month, int year, DayOfWeek dayToCount)
{
    DateTime dt = new DateTime(year, month, 1);
    int firstInstance = 1;
    if((int)dt.DayOfWeek > (int)dayToCount)
      firstInstance += (7 - (int)dt.DayOfWeek) + (int)dayToCount;
    else if((int)dt.DayOfWeek < (int)dayToCount)
      firstInstance += (int)dayToCount - (int)dt.DayOfWeek;
    return firstInstance <= (DateTime.DaysInMonth(month, year) - 28) ? 5 : 4;
}

harold aptroot wrote:

it looks like The Right Way to do it

public static int
F
(
    int              Year
,
    int              Month
,
    System.DayOfWeek DayOfWeek
)
{
    int d = (int) DayOfWeek - (int) (new System.DateTime ( Year , Month , 1 )).DayOfWeek ;

    if ( d < 0 )
    {
        d += 7 ;
    }

    int n = System.DateTime.DaysInMonth ( Year , Month ) - 28 ;

    return ( d < n ? 5 : 4 ) ;
}

int mondays=(DateTime.DaysInMonth(year, month) + (int)new DateTime(year, month, 6).DayOfWeek) / 7;

int Xdays=(DateTime.DaysInMonth(year, month) + (int)new DateTime(year, month, 7-dayOfWeek).DayOfWeek) / 7;

PIEBALDconsult wrote:

I expect the OP's teacher only wants to prove that he's smarter than his students

Member 4737022 wrote:

How can I read each line in that file?

string filePath = @"Path_to_your_file_here";
string line;

// Field lengths (I use the lengths from your original post):
int idLength = 5, snLength = 13, amountLength = 15, blankLength = 15;
 
if (File.Exists(filePath))
{
	StreamReader file = null;
	try
	{
		file = new StreamReader(filePath);
		while ((line = file.ReadLine()) != null)
		{
			// Extract fields from the line
                        string id = line.Substring(0, idLength);
			string sn = line.Substring(idLength, snLength);
			string amount = line.Substring(idLength + snLength, amountLength);
			string blank = line.Substring(idLength + snLength + amountLength, blankLength);
		}
	}
	finally
	{
		if (file != null)
		file.Close();
	}
} 

int id;
int sn;
double amount;
int blank;
StreamReader sr = new StreamReader("C:\FileFolder\myfile.txt");//
String strInput="";
strInput=sr.ReadLine();//Read first line in file
while ((strInput = sr.ReadLine()) != null ) //Read file rest of the file
{
     //Use Substring to extract specific portions of the string and assign value to the right variable
     try
     {
        id = int.Parse(strInput.Substring(0,5));
        sn=double.Parse(strInput.Substring(5,13));
       //etc
     }
     catch(Exception e)
     {


     }
}