#include <iostream>
#include <cmath>
#include <iomanip>
#include <fstream>

using namespace std;

//prototype for the user information function.
//prototype for the standard deviation function.
//prototype for function that finds the high value
//prototype for function that finds the low value
double findMean(const double list[], int numOfElements);
double findStdDev(const double list[], int numOfElements);
double findBiggest(const double list[], int size);
double findSmallest(const double list[], int size);

double findMean(double list[], int numOfElements)
{
    int index=0;
    double sum = 0;

    for (index = 0; index < numOfElements; index++)
        sum = sum + list[index];

	return sum / numOfElements;
}
///==================================================
double findStdDev(const double list[], int numOfElements){
   //lesse if i can get mean this way instead then
    int indexM=0;
    double sumM = 0;

    for (indexM = 0; indexM < numOfElements; indexM++)
        sumM = sumM + list[indexM];

    double mean = sumM;
    double numerator=0, stdDev=0;
    int index=0;

    for (index=0; index <numOfElements; index++)
        numerator = numerator + pow(list[index] - mean,2);

        stdDev = sqrt(numerator / numOfElements);
        return stdDev;
    }    // define the function to calculate standared deviation

///==================================================
double findSmallest(const double list[], int size){ // define the function to determine the smallest value
// in the array
    double smallest = list[0];
    for (int index =0; index<size; index++){
        if (list[index]<smallest){
            smallest = list[index];
        }
    }
    return smallest;
}

///==================================================
double findBiggest(const double list[], int size){ // define the function to determine the largest value
// in the array.
    double biggest = list[0];
    for (int index =0; index<size; index++){
        if (list[index]>biggest){
            biggest = list[index];
        }
    }
    return biggest;
}

///==================================================

///==================================================
int main()
{
    double numList[100];
    int count=0;  //total numbers read

    ifstream inFile;
	inFile.open("lab8input.txt");
	if(!inFile){
        cout <<"\n\nINPUT FILE ERROR!\n\n";
        return 1;
	}


	cout << fixed << showpoint << setprecision(2);

    inFile >> count;                //read the number of items
    cout << "************\n";               //loop and
    for(int index=0; index<count; index++){ //fill the array
       inFile >> numList[index];
     }

//////////////////////////////

    cout << "\nThe mean value is equal to: "<< findMean(numList, count);
    cout << "\nThe standard deviation is equal to: "<< findStdDev(numList, count);
    cout << "\nThe largest value equals: " << findBiggest(numList, count);
    cout << "\nThe smallest value equals: " << findSmallest(numList, count);

    inFile.close();
	return 0;
}
///==================================================