// Some examples that are somewhat like homework 1 as far as being
// wrong and yet close to working

#include <iostream.h>

// Purpose: A function to return the sum of the elements of the integer array
// Parameters: list = array of integers, size = length of the array
// Returns: sum of the numbers in list
// Bug: Works only if the last number happens to be the sum
//      (everything else adds up to 0)
int
sum(int * list, int size)
{
  int result = 0;

  for (int i = 0; i < size; i++)
    result = list[i];

// another possibility to get the same problem is
// the following loop body:
// {
//   result = 0;
//   result = result + list[i];
// }

  return result;
}

// Purpose: Another function to return the sum of the elements of the
//          integer array
// Parameters: list = array of integers, size = length of the array
// Returns: sum of the numbers in list
// Bug: Works only if the first number happens to be 0
int
sum2(int * list, int size)
{
  int result = 0;

  for (int i = 1; i < size; i++)
    result = result + list[i];

  return result;
}

// Purpose: Print out the numbers in the array on a line
//          Does not end with an end-of-line character
// Parameters: list = array of integers, size = length of the array
// Returns: nothing
// Bug :) Not really good if the list of numbers is too big to fit on a line
void printarray(int * list, int size)
{
  for (int i = 0; i < size; i++)
    cout << ' ' << list[i];
}

int main()
{
  // Array where last element is the sum
  int v1[4] = { 8, -15, 7, 20 };
  const int V1SIZE = sizeof(v1)/sizeof(int);
  // Array where first element is 0
  int v2[5] = { 0, -1, 7, 2, 3 };
  const int V2SIZE = sizeof(v2)/sizeof(int);

  // Displaying the data to make it easier to check if the results
  // satisfy the requirements
  cout << "v1 = ";
  printarray(v1, V1SIZE);
  cout  << endl;

  cout << "v2 = ";
  printarray(v2, V2SIZE);
  cout  << endl;

  cout << "--------------------------------" << endl;
  cout << "PROBLEM 1" << endl;
  cout << "--------------------------------" << endl;
  // correctly handles case where last element is sum
  cout << "The sum of v1 = " << sum(v1, V1SIZE) << endl;
  // incorrectly handles case where last element is not the sum
  cout << "The sum of v2 = " << sum(v2, V2SIZE) << endl;

  cout << "--------------------------------" << endl;
  cout << "PROBLEM 2" << endl;
  cout << "--------------------------------" << endl;
  cout << "The sum of v1 = " << sum2(v1, V1SIZE) << endl;
  cout << "The sum of v2 = " << sum2(v2, V2SIZE) << endl;
}