#include <iostream>
#include <fstream>
#include <iomanip>
using namespace std;

void ReadInput(ifstream &, int [], float [], int&);
void Print(ofstream &, int [], float [], int&);
void BubbleSort(int [], float [], int &);
void ExchangeSort(int [], float [], int &);
void FindLowScore(float [], int &, int &);
void FindHighScore(float [], int &, int &);
void CalculateSum(float [], int &, float &);
void PrintScores(ofstream &,float [], int [], int &, int &, float &, int &);
void Footer(ofstream &);
void Header(ofstream &);

int main()
{
ifstream input ("DATA3.TXT", ios::in);
ofstream output ("OUTPUT", ios::out);
output.setf(ios::fixed);
output.precision(1);
int studentIDs[50]; //creates an array with fifty integer places for student id's
float testScores[50]; //creates an array with fifty float places for test scores
int EU;
float sum;
int highScore = 0; //Initialize highScore to zero
int lowScore = 0; //Initialize lowScore to zero

Header(output);
ReadInput(input, studentIDs, testScores, EU);


//Print out the original list of IDs and Scores
output << "The original list of test scores is: "<< endl;
output << endl;
output << setw(6) << "Student ID #" << setw(12) <<"Test Score" << endl;
Print(output, studentIDs, testScores, EU);
output << endl;

//Sort from High to low based on test scores
BubbleSort(studentIDs, testScores, EU);

//Print out the updated list of IDs and Scores
output << "The test scores sorted highest to lowest are: "<< endl;
output << endl;
output << setw(6) << "Student ID #" << setw(12) <<"Test Score" << endl;
Print(output, studentIDs, testScores, EU);
output << endl;


//Sort from low to high based on IDs
ExchangeSort(studentIDs, testScores, EU);

//Print out the updated list of IDs and Scores
output << "The student ID numbers sorted lowest to highest are: "<< endl;
output << endl;
output << setw(6) << "Student ID #" << setw(12) <<"Test Score" << endl;
Print(output, studentIDs, testScores, EU);
output << endl;

//Find the lowest test score and corrresponding ID
FindLowScore(testScores, EU, lowScore);

//Find the highest test score and corresponding ID
FindHighScore(testScores, EU, highScore);

//Find the average test score
CalculateSum(testScores, EU, sum);

//Print out low score, high score, and average test score

PrintScores(output, testScores, studentIDs, lowScore, highScore, sum, EU);
Footer(output);
}

void ReadInput(ifstream &infile, int IDs[], float scores[], int &elementsUsed)
		// Recieveds - the inputfile, array of student IDs, array of test scores, and elements used
		// Task - reads in the IDs and test scores from a file
		// Returns - filled arrays
{
int num; 
float score;
elementsUsed = 0;
infile>>num; //read in the first student ID
infile>>score; //read in the first test score
while(num > 0) //Stay in loop while the placeholder value is greater than zero
{
	if(num < 0 || score < 0) //check to see that both inputs are greater than zero
		return;
	IDs[elementsUsed] = num; //place the first ID into the array of student IDs
	scores[elementsUsed] = score; //place the first test score into the array of test scores
	infile >>num; //read in the next ID
	infile >>score; //read in the next test score
	elementsUsed++;
}
return;
}

void Print(ofstream &outfile, int IDs[], float scores[], int &elementsUsed)
		// Recieves - the output file, array of student IDs, array of test scores, and elements used
		// Task - Prints the array of student IDs and test scores in columns
		// Returns - Nothing
{
int i;
for(i=0; i<elementsUsed; ++i) //continue in this loop until there are no more values
{
	// print the student id's and test scores on the same line with equal spacing
	outfile << setw(5) << IDs[i]<<" "; 
	outfile << setw(15)<< scores[i];
	outfile << endl;
}
return;
}

void BubbleSort(int IDs[], float scores[], int &EU)     // Sorts list high to low
{
int M, N;
float temp, temp2;
for ( M = 0 ; M < EU-1; M++) // Loop through every element in the array
 {
	 for ( N = EU-1; N > M ; N--) // Test each element from the end to the beginning
        {
		if (scores[N] > scores[N-1] ) // Compare each element and swap if necessary
        {
		 temp = scores[N]; //place the index of the score in a temporary variable
		 temp2 = IDs[N]; //place the index of the ID in a temporary variable
         scores[N] = scores[N-1]; // decrement the value of N for test scores
		 IDs[N] = IDs[N-1]; // decrement the value of N for the ID number
         scores[N-1] = temp; //place the new index of scores into the temporary variable
		 IDs[N-1] = temp2; //place the new index of ID number into the temporary variable
		}
        }
  }
   return;  
}     

void ExchangeSort(int id[], float test[], int &EU)
{
        // Recieves - The array of student IDs, array of test scores, and elements used
        // Task - Sorts the array from lowest ID number to highest ID number
        // Returns - The sorted arrays.
int M,N, Max;
float temp, temp2;
 for ( M = 0 ; M < EU-1; M++) // Loop through every element in the array
 {
  Max = M;
	  for ( N =EU-1 ; N>M ; N--) // Test each element from the end to the beginning
		 {
		 if (id[N] > id[Max] ) // Compare each element and swap if necessary
         {
			temp = id[N]; //place the index of the ID in a temporary variable
		 }
			temp2 = test[N]; //place the index of the score in a temporary variable
			id[N] = id[Max]; //Place the max value index into the running ID index
			test[N] = test [Max]; // Place the max value index into the running test score index
			id[Max] = temp; //Place the max index into the ID temporary variable
			test[Max] = temp2; //Place the max index into the test score index
		 
		 }		
 }
 return;
}          

void FindLowScore(float scores[], int &elementsUsed, int &ls)
		// Recieves - the array of test scores, elements used, and the low score
		// Task - Finds the lowest score location in the array of test scores
		// Returns - The lowest score location in the array
{
int i;
int minVal = 110; //Initialize a minimum value that is greater than the maximum value, which is 100
ls = 0;
for(i=0; i<elementsUsed; i++) //Continue in the loop until each value read in has been checked
{
	if(minVal > scores[i]) //Check to see if the minimum value is greater than the current array value 
	{
		minVal = scores[i]; //Replace the minimum value with the current array value
		ls = i; //Replace the index location of the minimum with the value assigned to ls 
	}
}
return;
}

void FindHighScore(float scores[], int &elementsUsed, int &hs)
		// Recieves - The array of student IDs, elements used, and the high score
		// Task - Finds the highest score location in the array of test scores
		// Returns - The highest score location in the array
{
int i;
int maxVal = -1; //Initialize a maximum value that less than the minimum value, which is 0
for(i=0; i<elementsUsed; i++) //Continue in the loop until each value read in has been check
{
	if(maxVal < scores[i]) //Check to see if the maximum value is less than the current array value
	{
		maxVal = scores[i]; //Replace the maximum value with the current array value
		hs = i; //Replace the index location of the maximum with the value assigned to hs 
	}
}
return;
}

void CalculateSum(float scores[], int &elementsUsed, float &total)
		// Recieves - the array of scores, elements used, and the total
		// Task - Compute the total sum of all the test scores
		// Returns - The sum of all the test scores
{
int i;
total = 0;

for(i=0; i<elementsUsed; ++i) //Check each value read in
{
	total += scores[i]; //Add the test score in the current array value to total
}
total=total/elementsUsed;
return;
}

void PrintScores(ofstream &outfile, float scores[], int id[], int &low, int &high, float &sum, int &EU)
		// Recieves - the array of scores, the min, the max, the sum, and the elements used
		// Task - Prints out the min score, max score, the average, and the elements used
		// Returns - The sum of all the test scores
{
//print the lowest test score and corresponding ID number
outfile << "The lowest test score was " << scores[low] <<" achieved by student #"<< id[low] << endl;
outfile << endl;
// print the highest test score and corresponding ID number
outfile << "The highest test score was " << scores[high] <<" achieved by student #"<< id[high] << endl;
outfile << endl;
// print the average test score of all the scores in the array 
outfile << "The average test score for the group is " << sum << endl;
return;
}