[AdamSpeight2008]

Mini Challenge: How Many Days Into Year

Challenge:

Create a function the returns how many days into year a user specified date.
Throw exception for an invalid date.

Function DaysInToYear(D As Integer,
                      M As Integer,
                      Y As Integer) As Integer
  Return  ' To be filled in '
End Function

Example Test Cases

01/01/2012 => 1
31/12/2012 => 366
30/12/2011 => 364

Restrictions
Use of the programming language's built-in date methods and functions, is prohibited.

Score
Least number of non whitespace characters, excluding the following allowances.

Allowances
The function definition signature and structure and the required return keyword.
What is provided above excluding the comments.

This post has been edited by AdamSpeight2008: 04 October 2012 - 10:17 AM

[Curtis Rutland]

Quick question: do we have to determine if the year is a leap year without using System.DateTime.IsLeapYear?

[AdamSpeight2008]

Is that one of the built-in date functions?

[Curtis Rutland]

Just double checking.

[Skydiver]

Here's my entry at a hefty 127 characters.

It also doesn't throw an exception for D being out of range, M being out of range, or negative years. It also doesn't check for special years when the number of days in a month were changed because some Roman emperor or another was feeling feisty, or when the shift from Julian to Gregorian calendar happened for a particular country or the world for that matter.

Spoiler

    Function DaysInToYear(D As Integer,
                          M As Integer,
                          Y As Integer) As Integer
        Dim r = {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30}
        For i = 0 To M - 1
            D = D + r(i)
        Next
        D = D + IIf(M > 2 AndAlso
                    (Y Mod 400 = 0 OrElse
                     (Y Mod 100 <> 0 And
                      Y Mod 4 = 0)),
                    1, 0)
        Return D
    End Function

(Forgive me if I've murdered the VB.NET language since I usually just read VB.NET, not write in it.)

[AdamSpeight2008]

My effort which I'll count later.

Spoiler

Function DaysInYear(D As Integer,
                    M As Integer,
                    Y As Integer) As Integer
  Dim s={0.31,28,31,30,31,30,31,31,30,31,30,31}
  s(2)+=If(M>2 And (Y Mod 4=0) And (Y Mod 400)>0),1,0)
  If (0<M And M<13) And (0 < D And D<= s(M)) Then Return s.Take(M).Sum + D
  Throw New ArgumentException("Invalid Date")
End Function

This post has been edited by AdamSpeight2008: 04 October 2012 - 12:09 PM
Reason for edit:: Missing New Keyword. So now 186

[Curtis Rutland]

My attempt in C#, like Skydiver's it doesn't check for invalids. I'll add that later. (118 chars):

Spoiler

private static int DaysInToYear(int d, int m, int y)
{
    int[] o = { 0, 3, 0, 1, 0, 1, 0, 0, 1, 0, 1, 0 };
    return o.Take(m - 1).Select(i => 31 - i).Sum() + d + ((m > 2 || d == 29) & y % 4 == 0 & (y % 100 != 0 || y % 400 == 0) ? 1 : 0);
}

Edit 1: By my count Adam, yours is 183. And damn, we had similar solutions again.

Edit 2: I realized mine is actually incorrect. Stand by.

Fixed, in at 109 chars:

Spoiler

private static int DaysInToYear(int d, int m, int y)
{
    int[] o = { 0, 3, 0, 1, 0, 1, 0, 0, 1, 0, 1, 0 };
    return o.Take(m - 1).Select(i => 31 - i).Sum() + d + (m > 2 & y % 4 == 0 & (y % 100 != 0 || y % 400 == 0) ? 1 : 0);
}

Last edit, changed my methodology slightly to get 102. The code looks more like yours, but I had always intended to try both ways to see which used more characters, a delta or a month list.

Spoiler

private static int DaysInToYear(int d, int m, int y)
{
    int[] o = { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
    return o.Take(m - 1).Sum() + d + (m > 2 & y % 4 == 0 & (y % 100 != 0 | y % 400 == 0) ? 1 : 0);
}

This post has been edited by Curtis Rutland: 04 October 2012 - 02:53 PM

[grimpirate]

Well, I didn't write this in VB.NET (as I haven't used it in a really long while), but I liked the challenge and I wanted to see what it would look like so I wrote it up in Java.

Spoiler

public static int daysElapsed(int D, int M, int Y) throws Exception{
	if(Y < 0) throw new Exception();
	if(M < 0 || M > 12)	throw new Exception();
	int sum = 0;
	int[] calendar = {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30};
	if(Y % 100 == 0 && Y % 400 == 0)
		calendar[2]++;
	else if (Y % 4 == 0 && Y % 100 != 0)
		calendar[2]++;
	if(D < 0 || D > calendar[M]) throw new Exception();
	for(int i = 1; i < M; i++)
		sum += calendar[i];
	return sum + D;
}

I have no idea what the spoiler tag is, but since it's in Java I figured it wouldn't be a problem.

This post has been edited by AdamSpeight2008: 04 October 2012 - 01:37 PM
Reason for edit:: Adding in the spoiler tags

[lucky3]

My entry. Didn't count number of characters, and check for input date validity.

Spoiler

    Function DaysInToYear(D As Integer,
                      M As Integer,
                      Y As Integer) As Integer
        Return (M - 1) * 30 - If(Y Mod 4 = 0, If(M > 2 Or (M = 2 And D = 29), 1, 0), 2) + D + (Function(f)
                                                                                                    Dim x = 0
                                                                                                    For n = 0 To M - 1
                                                                                                        x += If(f.Contains(n), 1, 0)
                                                                                                    Next
                                                                                                    Return x
                                                                                                End Function)(({1, 3, 5, 7, 8, 10, 12}).ToList)
    End Function

Edit: Hmmmm... I understood it should have just Return.....
Edit2: Missed the date validity check requirement. Will fix that. Fixed >=28 bug.

This post has been edited by lucky3: 04 October 2012 - 01:32 PM

[AdamSpeight2008]

I counted my original at 256 - (78 of allowances) => 178

Spoiler

  Function DaysInYear(D As Integer,
                      M As Integer,
                      Y As Integer) As Integer
    Dim s = {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}
    If (0 < M And M < 13) And (0 < D And D <= s(M)) Then Return s.Take(M).Sum + D + If(M > 2 And (Y Mod 4 = 0) And (Y Mod 400) > 0, 1, 0)
    Throw New ArgumentException("Invalid Date")
  End Function

173c

[lucky3]

Added date validation. It checks for leap year first, so it doesn't throw exception for 29th of February on leap year.

Spoiler

    Function DaysInToYear(D As Integer,
                      M As Integer,
                      Y As Integer) As Integer
        Return (Function(p, ex) If((p(M - 1) >= D Or D < 1) Or (M > 12 Or M < 1), (M - 1) * 30 - If(Y Mod 4 = 0, If(M > 2 Or (M = 2 And D > 29), 1, 0), 2) + D + (Function(f)
                                                                                                                                                                      Dim x = 0
                                                                                                                                                                      For n = 0 To M - 1
                                                                                                                                                                          x += If(f.Contains(n), 1, 0)
                                                                                                                                                                      Next
                                                                                                                                                                      Return x
                                                                                                                                                                  End Function)(({1, 3, 5, 7, 8, 10, 12}).ToList), ex))((Function(k)
                                                                                                                                                                                                                             If Y Mod 4 = 0 Then
                                                                                                                                                                                                                                 k(1) += 1
                                                                                                                                                                                                                             End If
                                                                                                                                                                                                                             Return k
                                                                                                                                                                                                                         End Function)({31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}), New Exception("Wrong parameters."))
    End Function

Fat 338c, obfuscator award?! (for serious attempt not to, but to stay with Returns... only)

This post has been edited by lucky3: 04 October 2012 - 03:31 PM

[Skydiver]

I've got it down to 46 characters including throwing exceptions for invalid dates:

Spoiler

    Function DaysInToYear(D As Integer,
                          M As Integer,
                          Y As Integer) As Integer
        Return (New DateTime(Y, M, D) - New DateTime(Y, 1, 1)).Days + 1
    End Function

The restriction was:

Quote

Use of the programming language's built-in date methods and functions, is prohibited.

VB's built in date method and function is through the use of Date. DateTime belongs to the CLR. (Of course, Date maps to DateTime, but the restriction was only the language not the CLR.)

This post has been edited by Skydiver: 04 October 2012 - 04:18 PM

[Curtis Rutland]

Clever, but obviously violating the spirit of the challenge, if not the letter.

[Skydiver]

80 Characters with no parameter checks and sticking to the spirit and letter of the restrictions:

Spoiler

    Function DaysInToYear(D As Integer,
                          M As Integer,
                          Y As Integer) As Integer
        Return D + If(M <= 2,
                      31 * (M - 1),
                      Int(30.6 * M - 91.4) +
                      If(Y Mod 400 = 0 Or (Y Mod 100 <> 0 And Y Mod 4 = 0),
                         60, 59))
    End Function

[lucky3]

If I may point out: the code should check if 29/2/2010 (non leap year) is valid first, and then do the magic.