e-olymp
Competitions

Week 11: February 1 - 7. Linked Lists

LinkedList Sum

Given a linked list, find the sum of its elements.

Definition of a single linked list:

// Java
class ListNode {
  int val;
  ListNode next;
  ListNode(int x) {
    val = x;
    next = null;
  }
}
// C++
class ListNode
{
public:
  int val;
  ListNode *next;
  ListNode(int x) : val(x), next(NULL) {}
};
// C
struct ListNode
{
  int val;
  struct ListNode *next;
};

Implement function sum that finds the sum of linked list elements.

// Java
int sum(ListNode head)
// C, C++
int sum(ListNode *head)

Example

prb9898.gif

The sum of elements of a linked list is 6.

Time limit 1 second
Memory limit 128 MiB
Author Mykhailo Medvediev