Compiler error with array/string initialization

[klatu375]

The compiler returns the following error when I try to compile any programs with an initialized string or array:
"extended initializer lists only available with -std=c++0x or -std=gnu++0x"

When I use the "-std" options, I would get something like this:
"invalid conversion from ‘const char*’ to ‘char’"

Below is the latest program I was working on that finally prompted me to post this question. The error is in the constructor on line 23; the initialization of month[]:

#include <iostream>
#include <cstdlib>

using namespace std;

class DayOfYear
{
private:
    int julianDay;
    // UPDATE: previously "string month[12]".
    static const string month[12];

public:
    DayOfYear( int );
    void setJulianDay( int );
    void print();
};

// UPDATE: month is a static const and properly initialized per ne555 posts.
const string DayOfYear::month[12] = { "January", "February", "March", 
                                      "April", "May", "June", "July", 
                                      "August", "September", "October", 
                                      "November", "December" };

DayOfYear::DayOfYear( int day = 1 )
{
    julianDay = day;
/* WRONG
    month[12] = { "January", "February", "March", 
                  "April", "May", "June", "July", 
                  "August", "September", "October", 
                  "November", "December" };
*/
}

void DayOfYear::setJulianDay( int jd )
{
    if ( jd > 0 && jd < 365 )
	julianDay = jd;
    else
    {
	cout << "Invalid Julian Day. Terminating program...\n";
	exit(EXIT_FAILURE);
    }
}

void DayOfYear::print()
{
    if ( julianDay <= 31 ) // UPDATE: Fixed out of bounds subscripts as ne555 pointed out.
	cout << month[0] << " " << julianDay;
    else if ( julianDay <= 59 )
	cout << month[1] << " " << julianDay - 31;
    else if ( julianDay <= 90 )
	cout << month[2] << " " << julianDay - 59;
    else if ( julianDay <= 120 )
	cout << month[3] << " " << julianDay - 90;
    else if ( julianDay <= 151 )
	cout << month[4] << " " << julianDay - 120;
    else if ( julianDay <= 181 )
	cout << month[5] << " " << julianDay - 151;
    else if ( julianDay <= 212 )
	cout << month[6] << " " << julianDay - 181;
    else if ( julianDay <= 243 )
	cout << month[7] << " " << julianDay - 212;
    else if ( julianDay <= 273 )
	cout << month[8] << " " << julianDay - 243;
    else if ( julianDay <= 304 )
	cout << month[9] << " " << julianDay - 273;
    else if ( julianDay <= 334 )
	cout << month[10] << " " << julianDay - 304;
    else
	cout << month[11] << " " << julianDay - 334;
}

int main()
{
    int day;
    DayOfYear date;
    
    cout << "\nPlease enter a Julian Day: ";
    cin >> day;

    date.setJulianDay( day );
    date.print();
    cout << endl << endl;
    
    return 0;
}

I've tried using a the shell command "g++ program.cpp" and "g++ program.cpp -std=c++0x" as well as the gnu++0x option. I've also tried to compile the program with codeblocks. g++ and codeblocks return the same error.

[ne555]

string month[12]; //an array of 12 elements (strings)
month[12]; //one string. (actually is an invalid dereference, out of bounds) 

I think that the name of the months is common to all instances. So

class DayOfYear{
  static const string month[12];
};

const string DayOfYear::month[12] = {"Jan", "Feb", /**/};

[klatu375]

Thank you ne55. That worked perfectly. I wish I realized that when I was breaking my head for a couple of hours trying to figure it out. Thanks for pointing out my out of bounds subscripts as well :)

Another question: You decided to declare the variable a const to protect its data from being change, but it could have worked just as well without it, right?

Also it seems a little contradicting to me that a const variable can't be altered after its declaration, but variables in a class can't be declared and initialized at the same time. I see how the initialization takes place after the class definition by making it static. Can you help me understand how is that possible with a constant?

[ne555]

I'm not sure if I understand you.
You set the value of constants in the constructor.

class foo{
  const int some_constant;
public:
  foo(int n): some_constant(n){} //initialization list
};

[klatu375]

Thank you for the extra information. I'm still new to the subject, but I'm sure I'll fully grasp it in time. Your replies certainly helped me understand it much better.