You must assign the grades for a programming class. Right now the class is

studying recursion, and students have been given this simple assignment: Write

a recursive method sumSquares that takes a reference to a linked list of Integer elements and returns the sum of the squares of the elements. The list nodes are of class LLNode . The objects in the list are all of class Integer.

Example:

Assume that the list is not empty.

You have received quite a variety of solutions. Grade the methods below, marking errors where you see them.

a)

int sumSquares ( LLNode list )

{

return 0;

if ( list != null )

return ( list.getInfo( )

* list.getInfo( )

+ sumSquares ( list.getLink( ) ) ) ;

}

b)

int sumSquares ( LLNode list )

{

int sum = 0;

while ( list != null )

{

sum = list.getInfo( ) + sum;

list = list.getLink( ) ;

}

return sum;

}

c)

int sumSquares ( LLNode list )

{

if ( list == null )

return 0;

else

return list.getInfo( ) * list.getInfo( )

+ sumSquares ( list.getLink( ) ) ;

}

d)

int sumSquares ( LLNode list )

{

if ( list . getLink( ) == null )

return list.getInfo( ) *

list.getInfo( ) ;

else

return list.getInfo( ) * list.getinfo( )

+ sumSquares ( list.getLink( ) ) ;

}

e)

int sumSquares ( LLNode list )

{

if ( list == null )

return 0;

else

return ( sumSquares ( list.getLink( ) ) *

sumSquares ( list.getLink( ) ) ) ;

}

list 1 S s umSquares(1ist) yields (5 5)(2 *2)+33)+(1 *1) 39