A program to help teachers average grades

scoreAverageProgram.cpp

//The purpose of the original assignment was to create a program that would
//allow teachers to input three test scores, and get the average of
//those three. I've altered it quite a bit, and the current version includes
//my first attempt at vectors (just taught myself how to use them today.)
//Planning on eventually making the averages be stored/retreivable.

//Also note that I follow the whitespace convention of indenting
//loops and if statements in entirety, and again for the body.

#include <iostream>
#include <iomanip>
#include <vector>
//#include <typeinfo>
//#include <cmath>
//#include <string>

using namespace std;

double getTestScore (int tck);
void getSubScript (int &sub);
void numOfStudentsQry (int &sentinel, int &pass);
void averagesYesOrNo(char &ynb);
void noFail ();

int main()
{
	int sent = 0;
	int firstPass = 0;
	numOfStudentsQry (sent,firstPass); //asks how many students teacher'll be grading - same var as where sentValue can be declared.
	
	vector<double>averages(firstPass, 0.0);
	vector<string>names(firstPass, "");

		while (sent > 0)//primary loop
		{

			string stuName = " ";
			cout << endl << "Enter student name/ID: ";
			getline (cin,stuName); //prompt for student name to tag average score/w
			names.erase(names.begin()+(sent-1));
			names.insert(names.begin()+(sent-1), stuName);

			int subScr = 0;
      
      			getSubScript (subScr);//asks user for cin >> of subscript variable
      
				if (subScr < 0)//if sentValue has been called, end program
				{
					sent = -1;
					break;
				}

			vector<double> score (subScr, 0.0);
				//score.reserve(subScr);
				//score.resize(subScr, 0.0);

				for (int tick = subScr-1; tick > -1; tick -= 1)//define values for vector
				{
					score.erase(score.begin()+tick);
					score.insert(score.begin()+tick, getTestScore(tick)) ;//asks for a cinput for each vector data location
						if (score.at(tick) < 0)//if sentValue has been called, end program
						{
							sent = -1;
							break;
						}//end if
				}//end for

			double sum = 0.0;
			int tack = subScr;
				for (tack = subScr-1; tack > -1; tack -= 1)//gets sum of all data locations in the vector
				{
					sum += score.at(tack);
				}
			
			double avg = sum/subScr;//calculates average, assigns to last spot in the array
			cout << "                    Average score for " << names.at(sent-1) << ", ID #" << sent << ": " << fixed << setprecision(1) << avg << endl;
			
			averages.erase(averages.begin()+(sent-1));
			averages.insert(averages.begin()+(sent-1), avg);
			sent -= 1;
			
				if (sent == 0)//checks for normal end of loop, lets user view averages
				{
					char yN = ' ';
					averagesYesOrNo(yN);//asks if they would like to view the averages they just calc'ed
					
						if (yN == 'Y')
						{	int eenie = firstPass;
						 
								for (; eenie > 0; eenie -= 1)
								{
									cout << names.at(eenie-1) <<  ", ID #" << eenie << ": " << averages.at(eenie-1) << endl;
								}//end for
						}//end inner if
				}//end outer if
				
			int meenie = firstPass;
      			numOfStudentsQry(sent, firstPass);//asks if they would like to use the program more if program would end normally	
				if (meenie != firstPass && firstPass > 0)//checks if new session has begun, so resets/sized vectors
				{
					averages.resize(firstPass, 0.0);
					names.resize(firstPass, "");
				}
		} //end while

	return 0;
}

double getTestScore (int tck)
{
	double score = 0.0001;
		while(score >  0.00001 && score < 0.0002)
		{
		    cout << endl << "Enter score #" << tck+1 << ": ";
		    cin >> score; noFail();
		}//end while
	return score;
}

void getSubScript (int &sub)
{
		while (sub == 0)//while loop ensures correct input, allows for sValue
		{
		cout << endl << "Enter the # of test scores to average: ";
		cin >> sub; noFail();
		}//end while
}

void numOfStudentsQry (int &sentinel, int &pass)
{
		while (sentinel == 0)//chance to edit sentine value
		{
			cout << endl << "Enter # of students you'll be grading (any -integer ends): ";
			cin >> sentinel; noFail();//define sentinel value for while
			pass = sentinel;
		}//end while
	
}

void averagesYesOrNo(char &ynb)
{
		while (ynb != 'Y' && ynb != 'N')
		{
			cout << endl << "Would you like to view the averages for this session? (y/n)";
			cin >> ynb; noFail();
			ynb = toupper(ynb);
			cout << endl;
		}
}
  
void noFail ()
{
	std::cin.clear();
	std::cin.ignore(65536,'\n');
}