/*
 *          File: sum2.cpp
 *        Author: Robert I. Pitts <rip@cs.bu.edu>
 * Last Modified: February 2, 2000
 *         Topic: Debugging Run-Time Errors without a Debugger
 * ----------------------------------------------------------------
 *
 * Usage:
 * =====
 * The user enters numbers separated by spaces, with 0 (zero)
 * entered as the last number.  Then, the sum of those numbers
 * is displayed.
 */

#include <iostream.h>


/************************ Function Prototypes *********************/

// PrintValues: Prints the values with +'s between each.
void PrintValues(float values[], int howmany);

// SumValues: Returns the sum of the values.
float SumValues(float values[], int howmany);

/*************************** Main Function *************************/

int main()
{
  const int MAX_VALUES = 10;  // Can deal with at most MAX_VALUES numbers.
  float values[MAX_VALUES];   // Array to hold the numbers.
  int howmany;                // How many numbers entered.

  cout << "Enter numbers to sum below (separated by spaces)." << endl
       << "Enter 0 (zero) as the last number." << endl;

  do {
    // Read the next number.
    cin >> values[howmany];

    // Increment the count.
    howmany++;  // Should error check "howmany"!

  } while (values[howmany-1] != 0);

  float sum = SumValues(values, howmany);

  cout << "The sum of ";
  PrintValues(values, howmany);
  cout << " is " << sum << endl;

  return 0;  // 0 means program exited successfully.
}


/************************ Function Definitions *********************/

void PrintValues(float values[], int howmany)
{
  for (int i = 0; i < howmany; i++) {
    if (i != 0)       // Print "+" before all but first number
      cout << " + ";
    cout << values[i];
  }
}

float SumValues(float values[], int howmany)
{
  float sum = 0;

  for (int i = howmany; i > 0; i--) {
    sum += values[i];
  }

  return sum;
}