/* Erik Ferguson
   Assignment 7
   11.19.2000    */

// === Includes ===============================================================

#include <stdio.h>

// === Includes ===============================================================


// === Function Initializations ===============================================

void PrintArray(int[], int); // prints the array
int  SumArray(int[], int, int); // prints the sum of the first 10 values
int  sequential_search(int search_key, int list_size,
                       const int array_to_search[]); // searches an array
int  DelElement(int[], int, int); // deletes an element
int  InsElement(int[], int, int, int); // adds an element

// *** Function Initializations ***********************************************


// *** main *******************************************************************

int main()
{
 // Variable Declarations
 int a[20] = {14,17,23,26,33,38,39,41,52,56,0,0,0,0,0,0,0,0,0,0};
 int i,
 sum,
 n = 10,
 NumEls = 10,           // total number of elements in array a
 DeleteIndex,           // index of number to delete after searched
 InsertIndex = 3,       // index of number to insert at
 NumToInsert = 7,       // number to insert at InsertIndex
 x = 38;                // number to delete

 // Print out original value of a
 printf("\nArray at start of program:\n");
 PrintArray(a, NumEls);

 // Sum up the first n elements and output
 sum = SumArray(a, n, NumEls);
 printf("\nSum of the first %d elements: %d",n,sum);

 // Find the index of the number to delete, which is variable x
 DeleteIndex = sequential_search(x, NumEls, a);

 // If the index is not -1, the default value of index, then delete
 if(DeleteIndex != -1)
 {
  // Delete the element... store return value of list_size in NumEls
  NumEls = DelElement(a, DeleteIndex, NumEls);
  // Print out new array after deletion
  printf("\n\nAfter deletion of %d:\n", x);
  PrintArray(a, NumEls);
 } // end if(DeleteIndex != -1)
 else
  printf("\n%d Not found in array a[]! Deletion failed.\n", x);

 // Insert the element and store return value of list_size in NumEls
 NumEls = InsElement(a, NumToInsert, InsertIndex, NumEls);
 printf("\n\nAfter insertion of %d at index %d:\n", NumToInsert, InsertIndex);
 PrintArray(a, NumEls);

 return 0;
} // end main

// *** main *******************************************************************


// === FUNCTION DEFINITIONS ===================================================


// *** PrintArray *************************************************************

// Function to print the first NumEls elements of array b
void PrintArray(int b[], int NumEls)
{

 int i = 0;

 printf("Array a has %d elements: ",NumEls);

 for(i=0;i<NumEls;++i)
 {
  printf(" %d ", b[i]);
 }

}

// *** PrintArray *************************************************************


// *** SumArray ***************************************************************

// Function to return the sum of the first NumEls elements of array b
int SumArray(int b[], int n, int NumEls)
{
 int sum = 0,
 i;

 for (i=0;i<n;i++)
 {
  sum += b[i];
 }

 return sum;
}

// *** SumArray ***************************************************************


// *** sequential_search ******************************************************

// Function to find an element in an array
int sequential_search(int search_key, int list_size,
                      const int array_to_search[])
{
 int i,
 index = -1;

 for(i=0;i<list_size;i++)
  if(search_key == array_to_search[i])
  {
   index = i;
   break;
  } // end if
 return index;
}

// *** sequential_search ******************************************************


// *** DelElement *************************************************************

// Function to delete an element in an array; also decreases list_size
int DelElement(int a[], int index, int list_size)
{
 int i;

 for(i = index; i < list_size; i++)
  {
  a[i] = a[i + 1];
  // Make the current value equal to the following value.
  }

 // Total number of elements has decreased by one.
 return --list_size;
}

// *** DelElement *************************************************************


// *** InsElement *************************************************************

// Non-destructively inserts an element into an array and increments list_size
int InsElement(int a[], int NumToInsert, int index, int list_size)
{
 int i,
 temp,
 temp2;

 ++list_size; // increment list_size by one to reflect addition

 for(i = (index - 1); i < list_size; i++)
 {
  temp2 = a[i + 1];
  a[i + 1] = temp;
  ++i;
  temp = a[i + 1];
  a[i + 1] = temp2;
 }

 // Insert the element
 a[index] = NumToInsert;

 return list_size;

}

// *** InsElement *************************************************************