#include <iostream.h>
#include <iomanip.h>
#include <math.h>

float find_avg(int [], int);         // function prototype
float std_dev(int [], int, float);   // function prototype

int main()
{
  const int NUMELS = 10;
  int values[NUMELS] = {98, 82, 67, 54, 78, 83, 95, 76, 68, 63};
  float average, stddev;

  average = findAvg(values, NUMELS); // call the function
  stddev = stdDev(values, NUMELS, average); // call the function

  cout << "The average of the numbers is "
       << setw(5) << setiosflags(ios::showpoint)
       << setprecision(2) << average << endl;

  cout << "The standard deviation of the numbers is "
       << setw(5) << setiosflags(ios::showpoint)
       << setprecision(2) << stddev << endl;

  return 0;
}

float findAvg(int nums[], int numel)
{
  int i;
  float sumnums = 0.0;

  for (i = 0; i < numel; i++)  // calculate the sum of the grades
    sumnums = sumnums + nums[i];

  return (sumnums / numel);    // calculate and return the  average
}

float stdDev(int nums[], int numel, float av)
{
  int i;
  float sumdevs = 0.0;

  for (i = 0; i < numel; i++)
    sumdevs = sumdevs + pow((nums[i] - av),2);

  return(sqrt(sumdevs/numel));
}