/* This program defines four procedures -- total(), avg(), max() and man() -- that
   return single values calculated from a vector of doubles.  None of them use 
   reference parameters, so each one of them makes a copy of the vector, which is
   expensive.

   To test this, I shove some randomish values into a large vector, and then call
   all of them.  
 */

#include <cstdlib>
#include <cstdio>
#include <vector>
#include <sstream>
#include <iostream>
using namespace std;

/* This returns the total of the values. */

double total(vector <double> v)
{
  size_t i;
  double t;

  t = 0;
  for (i = 0; i < v.size(); i++) t += v[i];
  return t;
}

/* This returns the average of the values.  It does it by calling total to sum the values. */

double avg(vector <double> v)
{
  double size;

  size = v.size();
  return total(v)/size;
}

/* This returns the maximum of the values. */

double max(vector <double> v)
{
  size_t i;
  double mx;

  mx = v[0];
  for (i = 1; i < v.size(); i++) if (v[i] > mx) mx = v[i];
  return mx;
}

/* This returns the minimum of the values. */

double min(vector <double> v)
{
  size_t i;
  double mn;

  mn = v[0];
  for (i = 1; i < v.size(); i++) if (v[i] < mn) mn = v[i];
  return mn;
}

/* We call main() with the number of values in the vector. 
   We then create the vector, and call all of the procedures. */

int main(int argc, char **argv)
{
  int i;
  int n;
  istringstream ss;
  vector <double> v;
  double val;

  /* Parse the command line. */

  if (argc != 2) { cerr << "usage: total_etc_1 number-of-elements\n"; exit(1); }
  ss.str(argv[1]);
  if (!(ss >> n)) { cerr << "usage: total_etc_1 number-of-elements\n"; exit(1); }

  /* Create the vector -- I'm not using a random number generator here -- I'm 
     just starting with val = 10*1/7 and repeatedly squaring it, dividing by
     ten with it exceeds ten.  That will keep the values between 1 and 10, but
     looking kinda random. */

  val = 1/7.0 * 10.0;

  for (i = 0; i < n; i++) {
    v.push_back(val);
    val *= val; 
    if (val > 10) val /= 10.0;
  }

  /* Print the values if there are fewer than 10 */

  if (n < 10) {
    for (i = 0; i < n; i++) printf("%6.4lf\n", v[i]);
    printf("\n");
  }

  /* Call the procedures and print the results. */

  printf("Total: %12.4lf\n", total(v));
  printf("Avg:   %12.4lf\n", avg(v));
  printf("Max:   %12.4lf\n", max(v));
  printf("Min:   %12.4lf\n", min(v));
  return 0;
}