Task: Calendar
C#: using System;
using System.Collections.Generic; 
using System.Linq;
using System.Text;

namespace CalendarStuff
{
 
    class Program
    {
        static void Main(string[] args)
        {
            Console.WindowHeight = 46;
            Console.Write(buildMonths(new DateTime(1969, 1, 1)));
            Console.Read(); 
        }
        private static string buildMonths(DateTime date)
        {
            StringBuilder sb = new StringBuilder();
            sb.AppendLine(center("[Snoop]", 24 * 3));
            sb.AppendLine();
            sb.AppendLine(center(date.Year.ToString(), 24 * 3));

            List<DateTime> dts = new List<DateTime>();
            while (true)
            {
                dts.Add(date);
                if (date.Year != ((date = date.AddMonths(1)).Year))
                {
                    break;
                }
            }
            var jd = dts.Select(a => buildMonth(a).GetEnumerator()).ToArray();
            
            int sCur=0;
            while (sCur<dts.Count)
            {
                sb.AppendLine();
                int curMonth=0; 
                var j = jd.Where(a => curMonth++ >= sCur && curMonth - 1 < sCur + 3).ToArray(); 
                sCur += j.Length; 
                bool breakOut = false;
                while (!breakOut)
                {
                    int inj = 1;
                    foreach (var cd in j)
                    {
                        if (cd.MoveNext())
                        {
                            sb.Append((cd.Current.Length == 21 ? cd.Current : cd.Current.PadRight(21, ' ')) + "     ");
                        }
                        else
                        {
                            sb.Append("".PadRight(21, ' ') + "     ");
                            breakOut = true;
                        }
                        if (inj++ % 3 == 0) sb.AppendLine();
                    }
                }

            }
            return sb.ToString();
        }


        private static IEnumerable<string> buildMonth(DateTime date)
        {
            yield return center(date.ToString("MMMM"),7*3);
            var j = DateTime.DaysInMonth(date.Year, date.Month);
            yield return Enum.GetNames(typeof(DayOfWeek)).Aggregate("", (current, result) => current + (result.Substring(0, 2).ToUpper() + " "));
            string cur = "";
            int total = 0;

            foreach (var day in Enumerable.Range(-((int)date.DayOfWeek),j + (int)date.DayOfWeek))
            {
                cur += (day < 0 ? "  " : ((day < 9 ? " " : "") + (day + 1))) +" ";
                if (total++ > 0 && (total ) % 7 == 0)
                {
                    yield return cur;
                    cur = "";
                }
            }
            yield return cur;
        }
        private static string center(string s, int len)
        {
            return (s.PadLeft((len - s.Length) / 2 + s.Length, ' ').PadRight((len), ' '));
        } 
    }
}

C++: #include <windows.h>
#include <iostream>


using namespace std;



class calender
{
public:
    void drawCalender( int y )
    {
	year = y;
	for( int i = 0; i < 12; i++ )
	    firstdays[i] = getfirstday( i );

	isleapyear();
	build();
    }

private:
    void isleapyear()
    {
	isleap = false;

	if( !( year % 4 ) )
	{
	    if( year % 100 ) isleap = true;
	    else if( !( year % 400 ) ) isleap = true;
	}
    }

    int getfirstday( int m )
    {
	int y = year;

	int f = y + 1 + 3 * m - 1;
	m++;
	if( m < 3 ) y--;
	else f -= int( .4 * m + 2.3 );

	f += int( y / 4 ) - int( ( y / 100 + 1 ) * 0.75 );
	f %= 7;

	return f;
    }

    void build()
    {
	int days[] = { 31, isleap ? 29 : 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
	int lc = 0, lco = 0, ystr = 7, start = 2, fd = 0, m = 0;
	HANDLE h = GetStdHandle( STD_OUTPUT_HANDLE );
	COORD pos = { 0, ystr };
	draw();

	for( int i = 0; i < 4; i++ )
	{
	    for( int j = 0; j < 3; j++ )
	    {
		int d = firstdays[fd++], dm = days[m++];
		pos.X = d * 3 + start;
		SetConsoleCursorPosition( h, pos );

		for( int dd = 0; dd < dm; dd++ )
		{
		    if( dd < 9 ) cout << 0 << dd + 1 << " ";
		    else cout << dd + 1 << " ";

		    pos.X += 3;
		    if( pos.X - start > 20 )
		    {
			pos.X = start; pos.Y++;
			SetConsoleCursorPosition( h, pos );
		    }
		}

		start += 23;
		pos.X = start; pos.Y = ystr;
		SetConsoleCursorPosition( h, pos );
	    }
	    ystr += 9; start = 2;
	    pos.Y = ystr;
	}
    }

    void draw()
    {
	system( "cls" );
	cout << "+--------------------------------------------------------------------+" << endl;
	cout << "|                              [SNOOPY]                              |" << endl;
	cout << "|                                                                    |" << endl;
	cout << "|                             == " << year << " ==                             |" << endl;
	cout << "+----------------------+----------------------+----------------------+" << endl;
	cout << "|       JANUARY        |       FEBRUARY       |         MARCH        |" << endl;
	cout << "| SU MO TU WE TH FR SA | SU MO TU WE TH FR SA | SU MO TU WE TH FR SA |" << endl;
	cout << "|                      |                      |                      |" << endl;
	cout << "|                      |                      |                      |" << endl;
	cout << "|                      |                      |                      |" << endl;
	cout << "|                      |                      |                      |" << endl;
	cout << "|                      |                      |                      |" << endl;
	cout << "|                      |                      |                      |" << endl;
	cout << "+----------------------+----------------------+----------------------+" << endl;
	cout << "|        APRIL         |          MAY         |         JUNE         |" << endl;
	cout << "| SU MO TU WE TH FR SA | SU MO TU WE TH FR SA | SU MO TU WE TH FR SA |" << endl;
	cout << "|                      |                      |                      |" << endl;
	cout << "|                      |                      |                      |" << endl;
	cout << "|                      |                      |                      |" << endl;
	cout << "|                      |                      |                      |" << endl;
	cout << "|                      |                      |                      |" << endl;
	cout << "|                      |                      |                      |" << endl;
	cout << "+----------------------+----------------------+----------------------+" << endl;
	cout << "|         JULY         |        AUGUST        |       SEPTEMBER      |" << endl;
	cout << "| SU MO TU WE TH FR SA | SU MO TU WE TH FR SA | SU MO TU WE TH FR SA |" << endl;
	cout << "|                      |                      |                      |" << endl;
	cout << "|                      |                      |                      |" << endl;
	cout << "|                      |                      |                      |" << endl;
	cout << "|                      |                      |                      |" << endl;
	cout << "|                      |                      |                      |" << endl;
	cout << "|                      |                      |                      |" << endl;
	cout << "+----------------------+----------------------+----------------------+" << endl;
	cout << "|        OCTOBER       |       NOVEMBER       |       DECEMBER       |" << endl;
	cout << "| SU MO TU WE TH FR SA | SU MO TU WE TH FR SA | SU MO TU WE TH FR SA |" << endl;
	cout << "|                      |                      |                      |" << endl;
	cout << "|                      |                      |                      |" << endl;
	cout << "|                      |                      |                      |" << endl;
	cout << "|                      |                      |                      |" << endl;
	cout << "|                      |                      |                      |" << endl;
	cout << "|                      |                      |                      |" << endl;
	cout << "+----------------------+----------------------+----------------------+" << endl;
    }

    int firstdays[12], year;
    bool isleap;
};

int main( int argc, char* argv[] )
{
    int y;
    calender cal;

    while( true )
    {
	system( "cls" );
	cout << "Enter the year( yyyy ) --- ( 0 to quit ): "; 
	cin >> y;
	if( !y ) return 0;

	cal.drawCalender( y );
	cout << endl << endl << endl << endl << endl << endl << endl << endl;

	system( "pause" );
    }
    return 0;
}