Getting bizarre results from simple math

[mmyers1]

//Average scores
		else if ((Menu == 'B') || (Menu == 'b')){
			char AvgDone;
			double TotalGrade;
			double Grade;
			double AvgGrade;
			double NumOfGrades = 0;
			do{
			cout << "Please enter your grade" << endl;
			cin >> Grade;
			TotalGrade = TotalGrade + Grade;
			NumOfGrades = NumOfGrades + 1;
			cout << "Do you have more grades to enter? [Y]es or [N]o " << endl;
			cin >> AvgDone;
			} while((AvgDone == 'Y') || (AvgDone == 'y'));
			AvgGrade = TotalGrade / NumOfGrades;
			cout << "The average for the " << NumOfGrades << " grades given is " << AvgGrade << endl;
			cout << "Return to the menu? [Y]es or [N]o" << endl;
			cin >> Again;

Gives me the following results if I enter 100 for a single grade.

************************************************************
*       Plese choose from the following menu options       *
*       <A> Convert single numeric grade to alpha grade    *
*                                                          *
*       <B> Average numeric grades                         *
*                                                          *
*       <C> End Program                                    *
************************************************************
Enter your choice
b
Enter your numeric grade:
Please enter your grade
100
Do you have more grades to enter? [Y]es or [N]o
n
The average for the 1 grades given is -9.25596e+061
Return to the menu? [Y]es or [N]o

It seems to me this is simply 100 / 1 and therefore should be 100, or is this working with some 'new' math??

Thanks!!


By the way, yes, this is homework!

[elad]

always initialize variables. Otherwise you are likely to get junk where you don't want it. For example, totalGrade starts out with junk you don't initialize it. Then you add 1 to junk and you still have junk. Then you divide junk by more junk to get even more junk when you calculate avgGrade.

[mmyers1]

That fixed it!! WOOT! I love this site! Thanks elad....thanks a lot.....

[Jotun]

haha