Help Needed Fast! Multiple Choice Grading Program

Hey there,

I'm working on a program that grades multiple-choice exams. It compiles, but I keep getting a linking error, LNK2019: unresolved external symbol. I can't find this unresolved symbol, and I was wondering if someone else could. Or give some tips on how to fix it? And also, it's due in two hours, so quick help is appreciated!

Code:

Code:

#include <iostream>
#include <string>
#include <fstream>

using namespace std;

void OpenFiles (ifstream& inFile, ofstream& outFile);		
void WrongSize (ofstream& outFile, int keylength, string answers, string key);		
int main()
{
	
	ifstream inFile;
	ofstream outFile;
	OpenFiles(inFile, outFile);

	if (!inFile || !outFile)
	{
		cout << "Error opening files." << endl;
		return 1;
	}

	string key;
	string student;
	string answers;
	int keylength;

	inFile >> key;
	keylength = key.length();

	while(inFile >> student >> answers)
	{
		outFile << student << " ";
		WrongSize(outFile, keylength, answers, key);
	}

return 0;
}

//**************************************************************

void OpenFiles(ifstream& inFile, ofstream& outFile)
{
	string inFileName;
	string outFileName;
	cout << "Enter the name of the input file." << endl;
	cin >> inFileName;
	inFile.open(inFileName.c_str());

	cout << "Enter the name of the output file." << endl;
	cin >> outFileName;
	outFile.open(outFileName.c_str());
	outFile << "Scores for multiple-choice exam from " << inFileName << endl;
	outFile << fixed;
}

void WrongSize(ofstream& outFile, int keylength, string answers, string key)
{
	int grade = 0;
	bool check;

	if (answers.length() < keylength)
	{
		outFile << "Too few answers";
	}
	else if (answers.length() > keylength )
	{
		outFile << "Too many answers";
	}
	else
	{
		check = false;
	}

	for (int count = 0; count < key.length(); count++)
	{
	if( answers[count] == key[count] )
	{
		grade++;
	}
	else if (answers[count] != 'a' && answers[count] != 'b' && answers[count] != 'c' && answers[count] != 'd' && answers[count] != 'e' && answers[count] != 'f')
	{
		check = true;
	}

	if (check == true)
	{
		outFile << "Invalid Answer";
	}
	else
	{
		outFile << grade;
	}
}
outFile << endl;
}

it compiles ok for me apart from warnings about comparison of signed and unsigned ints, can you post a sample file to run it with?

Does it matter?
They wanted it "in 2 hours", and that deadline has long gone.