problem overloading + operator

[gasfusion]

I'm coding a program which calculates time values in hh:mm:ss format.
I'm reading times from a file containing 1 time string per line. After reading times, i continue reading operations on the time in the same file. operations are like this:
167+234

which basically means i take the 167th row in the file and add it with 234th.

here is what i have so far. Note the >> operator is also overloaded.

myClass operationAnswer, myArray[300]; // this is actually a dynamic array in my program.
int Index1, Index2;
char sign;
                // Assume i already read the times... Reading operations now
		while(!fin.eof() && fin >> Index1
								>> sign
								>> Index2) {
 if (sign == '+') 
   myAnswer = myArray[Index1] + myArray[Index2];
 else
  // do subtraction

And this is my overloaded + operator

DateProcessorClass operator + (DateProcessorClass& left, DateProcessorClass& right)
{
	/* Cannot pass by reference because we'll expose private variables */
	int resultSec, resultMin, resultHour;
	int tempMinutes, tempHours;

	resultSec = left.getSeconds() + right.getSeconds();
	tempMinutes = left.getMinutes();
	if (resultSec > 60)
	{
		resultSec = resultSec - 60;
		tempMinutes = left.getMinutes() + 1;
	}
	resultMin = tempMinutes + right.getMinutes();
	tempHours = left.getHours();
	if (resultMin > 60)
	{
		resultMin = resultMin - 60;
		tempHours = left.getHours() + 1;
	}
	resultHour = tempHours + right.getHours();
	return DateProcessorClass(resultHour,resultMin,resultSec);
}

When i try to compile i get this error:

main.obj : error LNK2019: unresolved external symbol "class DateProcessorClass __cdecl operator+(class DateProcessorClass const &,class DateProcessorClass const &)" (??H@YA?AVDateProcessorClass@@ABV0@0@Z) referenced in function _main
Debug/DateProcessorClass.exe : fatal error LNK1120: 1 unresolved externals

Any ideas?

[gasfusion]

errr... problem solved.
I was passing parameters as constants in my + operator function in the declaration of the function in the header file.

DateProcessorCl ass operator + (const DateProcessorCl ass& left, const DateProcessorCl ass& right);

Duh...