Write a program that inserts 25 random integers from 0 to 100 in order in a linked list ob- ject. The program should calculate the sum of the elements and the floating-point average of the elements.

Question

What will be an ideal response?

Answer 1

```
// List2 class template definition
// Enhances List by adding insertInOrder.
#ifndef LIST2_H
#define LIST2_H

#include "ListNode.h"
#include "List.h"

template< typename NODETYPE >
class List2 : public List< NODETYPE >
{
public:
void insertInOrder( const NODETYPE & );
}; // end class List2

// insert a node in order
template< typename NODETYPE >
void List2< NODETYPE >::insertInOrder( const NODETYPE &value )
{
if ( isEmpty() ) // list is empty
{
ListNode< NODETYPE > *newPtr = getNewNode( value );
firstPtr = lastPtr = newPtr;
} // end if
else // list is not empty
{
if ( firstPtr->getData() > value ) // value is the smallest
insertAtFront( value );
else if ( lastPtr->getData() < value ) // value is the largest
insertAtBack( value );
else
{
ListNode< NODETYPE > *currentPtr = firstPtr->getNextPtr();
ListNode< NODETYPE > *previousPtr = firstPtr;
ListNode< NODETYPE > *newPtr = getNewNode( value );

while ( currentPtr != lastPtr && currentPtr->getData() < value )
{
previousPtr = currentPtr;
currentPtr = currentPtr->getNextPtr();
} // end while

previousPtr->setNextPtr( newPtr );
newPtr->setNextPtr( currentPtr );
} // end else
} // end else
} // end function insertInOrder

#endif
```
```
#include
#include
#include
using namespace std;

#include "List2.h"

// integer specific list sum
int sumList( List2< int > &listRef )
{
List2< int > temp( listRef );
int sum = 0;
int value;

// until temp is empty
while ( !temp.isEmpty() )
{
temp.removeFromFront( value ); // remove from the front
sum += value; // add value to sum
} // end while

return sum;
} // end function sumList

// integer specific list average
double aveList( List2< int > &listRef )
{
List2< int > temp( listRef );
int sum = 0;
int value;
int count = 0;

// go through copy of listRef
while ( !temp.isEmpty() )
{
temp.removeFromFront( value ); // remove each element
count++; // increment the count
sum += value; // add into sum
} // end while

// return the average
return static_cast< double >( sum ) / count;
} // end function aveList

int main()
{
srand( time( 0 ) ); // randomize the random number generator

List2< int > intList;

// fill intList with 25 random numbers
for ( int i = 1; i <= 25; i++ )
intList.insertInOrder( rand() % 101 );

intList.print();

int sum = sumList( intList ); // calculate sum
double average = aveList( intList ); // calculate average

cout << "The sum of the elements is: " << sum << '\n';
cout << "The average of the elements is: " << average << '\n';
return 0; // indicates successful termination
} // end main
```
The list is: 2 4 14 23 31 33 33 36 43 52 53 56 56 67 73 76 81 81 82 83 90 93
95 98 98
All nodes destroyed
All nodes destroyed
The sum of the elements is: 1453
The average of the elements is: 58.12
Destroying nodes ...
2 4 14 23 31 33 33 36 43 52 53 56 56 67 73 76 81 81 82 83 90 93 95 98 98
All nodes destroyed