#include <iostream>
#include <fstream>
#include <iomanip>
#include <string>
using namespace std;
 
const int MAX_SIZE = 100;
 
void Fill_Array(int Size[], int& count, int& numbers_used);
void Print_Array(int Size[], int count);
double Calc_Average(int Size[], double average);
void Sort(int Size[], int numbers_used);
void Swap(int& v1, int& v2);
int index_of_smallest(const int Size[], int start_index, int number_used);
int Calc_Median(int median, int Size[]);
void Print_Array_and_Calculations(int median, double average);
 
int main()
{
	ifstream in_size;
	int count;
	int Size [MAX_SIZE],
	    numbers_used = 0,
	    median = 0;
	double average = 0.0;
 
	Fill_Array(Size, count, numbers_used);
	Print_Array(Size, count);
	average = Calc_Average(Size, average);
	Sort(Size, numbers_used);
	Calc_Median(median, Size);
	Print_Array_and_Calculations(median, average);
 
	in_size.close();
	return 0;
}
 
void Fill_Array(int Size[], int& count, int& numbers_used)
{
	int size;
	ifstream in_size;
	string text_file;
 
 
	cout << "Enter the file to read in: ";
	getline(cin, text_file);
 
	cout << endl << "The numbers in the array are:" << endl << endl;
	in_size.open (text_file.c_str ());
	if(in_size.fail())
	{
		cerr  << "Error opening file" << endl;
		exit(1);
	}
	count = 0;
	in_size >> size;
	while((!in_size.eof()) && (count <= MAX_SIZE))
	{
		Size[count] = size;
		count++;
		in_size >> size;
	}
	in_size.close();
}
 
void Print_Array(int Size[], int count)
{
	int number_used = 0;
	for(int index = 0; index < number_used; index++)
		cout << Size[index] << " ";
}
 
double Calc_Average(int Size[], double average)
{
	int total = 0;
	for (int i = 0; i < MAX_SIZE; i++)
	{
		total = total + Size[i];
	}
	average = double(total) / MAX_SIZE;
 
	return average;
}
 
void Sort(int Size[], int number_used)
{
	int index_of_next_smallest;
 
	for (int index = 0; index < number_used - 1; index++)
	{
		index_of_next_smallest = index_of_smallest(Size, index, number_used);
		Swap(Size[index], Size[index_of_next_smallest]);
	}
}
 
void Swap(int& v1, int& v2)
{
	int temp;
	temp = v1;
	v1 = v2;
	v2 = temp;
}
 
int index_of_smallest(const int Size[], int start_index, int number_used)
{
	int min = Size[start_index],
		index_of_min = start_index;
	for (int index = start_index + 1; index < number_used; index++)
		if(Size[index] < min)
		{
			min = Size[index];
			index_of_min = index;
		}
		return index_of_min;
}
 
int Calc_Median(int median, int Size[])
{
	median = Size [ MAX_SIZE / 2 ];
	return median;
}
 
void Print_Array_and_Calculations(int median, double average)
{
	cout << endl << "The average of the numbers is " << average;
	cout << endl << "The median of the numbers is " << median;
	cout << endl << endl;
}

#include <iostream>
#include <fstream>
#include <string>
#include <math.h>
#include <exception>
using namespace std;

// Parses the input file into the array's size and contents.
// Dynamically allocates memory for the array, fills it, and returns.
void parse_file(char * filename, double *&a, int &size) {
	ifstream myfile;
	myfile.exceptions( fstream::failbit );

	// Get the file name, and try to open the said file
	printf("Input the filename: ");   
	scanf("%s",filename);
	// Try opening the file, if it doesn't exist, throw an exception
	try {
		myfile.open(filename);
	} catch(ifstream::failure e) {
		printf("File does not exist or is unreadable\n");
	}

        // Read the first thing from the file as an int and store it as 'num'
	myfile>>size;

        // allocate an array to the exact that we need
        a = (double *) malloc(size*sizeof(double));
        // Fill the array
        for(int i=0; i<size; i++) {
		myfile>>a[i];
        }
	myfile.close();
}

// Standard way of calculating average
// Sums the elements of a, puts them into total, divides by size and returns.
double find_average(double *&a, int size) {
	double total = 0;
	for(int i=0; i<size; i++) {
		total = total + a[i];
	}
	return (total/(double)size);
}

// Standard way of calculating standard deviation
// Sums the square of each element minus the average
// Divides the total of squares by the size and returns the positive square root of the sum.
double find_standard_dev(double *&a, int size, double average) {
	double dev = 0;
	for(int i=0; i<size; i++) {
		dev = dev + pow(a[i]-average,2);
	}
	dev = dev/size;
	return (sqrt(fabs(dev)));
}

int main() {

	// Set up some variables
	char filename[50]; // 50 characters for the filename should be good enough unless the path is included.
	double average = 0, standard_dev = 0; // Zero out our variables before we start using them
	int num; // Array size
	double * array; // Make a pointer to our array

	parse_file(filename, array, num);

	average = find_average(array,num);

	standard_dev = find_standard_dev(array, num, average);

	printf("Average: %lf\n",average);
	printf("Standard Deviation: %lf\n",standard_dev);
	free(array);
	return 0;
}

void Print_Array(int Size[], int count)
{
	int number_used = 0;
	for(int index = 0; index < number_used; index++)
		cout << Size[index] << " ";
}