find the triplet sum in java linked list
// Java program to find a triplet from three linked lists with
// sum equal to a given number
class LinkedList
{
Node head; // head of list
/* Linked list Node*/
class Node
{
int data;
Node next;
Node(int d) {data = d; next = null; }
}
/* A function to chech if there are three elements in a, b
and c whose sum is equal to givenNumber. The function
assumes that the list b is sorted in ascending order and
c is sorted in descending order. */
boolean isSumSorted(LinkedList la, LinkedList lb, LinkedList lc,
int givenNumber)
{
Node a = la.head;
// Traverse all nodes of la
while (a != null)
{
Node b = lb.head;
Node c = lc.head;
// for every node in la pick 2 nodes from lb and lc
while (b != null && c!=null)
{
int sum = a.data + b.data + c.data;
if (sum == givenNumber)
{
System.out.println("Triplet found " + a.data +
" " + b.data + " " + c.data);
return true;
}
// If sum is smaller then look for greater value of b
else if (sum < givenNumber)
b = b.next;
else
c = c.next;
}
a = a.next;
}
System.out.println("No Triplet found");
return false;
}
/* Given a reference (pointer to pointer) to the head
of a list and an int, push a new node on the front
of the list. */
void push(int new_data)
{
/* 1 & 2: Allocate the Node &
Put in the data*/
Node new_node = new Node(new_data);
/* 3. Make next of new Node as head */
new_node.next = head;
/* 4. Move the head to point to new Node */
head = new_node;
}
/* Driver program to test above functions */
public static void main(String args[])
{
LinkedList llist1 = new LinkedList();
LinkedList llist2 = new LinkedList();
LinkedList llist3 = new LinkedList();
/* Create Linked List llist1 100->15->5->20 */
llist1.push(20);
llist1.push(5);
llist1.push(15);
llist1.push(100);
/*create a sorted linked list 'b' 2->4->9->10 */
llist2.push(10);
llist2.push(9);
llist2.push(4);
llist2.push(2);
/*create another sorted linked list 'c' 8->4->2->1 */
llist3.push(1);
llist3.push(2);
llist3.push(4);
llist3.push(8);
int givenNumber = 25;
llist1.isSumSorted(llist1,llist2,llist3,givenNumber);
}
} /* This code is contributed by Rajat Mishra */
