Question

a. Construct a RECURSIVE solution for following iterative solution to find a value in a circular-linked list

b. prove the correctness of your recursive solution by induction

/**
@param value - a value to search for
@return true if the value is in the list and set the current reference to it
otherwise return false and not updating the current reference
*/
public boolean find(T value){
if(this.cur == null)
return false; //get out, nothing is in here

Node tmp = this.cur; //start at the current position
if(tmp.data == value)
return true; // found it at the starting location

tmp = tmp.next; //adv. to next node, if there is one
while(tmp != cur) {
if(tmp.data == value){
this.cur = tmp; //update the cur reference to the found node
return true;
}

tmp = tmp.next
}
return false; //not found
}

Note: Please use Java

Answer 1

public boolean find(Node head , Node temp , T value) //pass head , head.next ,value

{

if(head==temp) return false; // termination condition if value is not present in entire list

if(head==null) return false; // if list is empty

if(head.data==value)return true; //if found at first position

if(temp.data==value)

{

this.cur=tmp; //if found then set current reference to it

return true;

}

find(head,temp.next,value); //recrusive call

}

/**

calling

find (head,head.next,value);

we pass the head pointer, and next value after head and the value to be searched.

*/