HackerRank - Find merge point

FindMergePoint2.cpp

/*
   Find merge point of two linked lists
   Node is defined as
   struct Node
   {
       int data;
       Node* next;
   }
*/

int length(Node* head)
{
    if(head==NULL)
        return 0;
    else return length(head->next)+1;
}

Node* position(Node* head, int pos)
{
    if(pos==0)
        return head;
    else return position(head->next, pos-1);
}

int common(Node* headA, Node* headB)
{
    if(headA==headB)
        return headA->data;
    else return common(headA->next, headB->next);
}

int FindMergeNode(Node *headA, Node *headB)
{
    // Complete this function
    // Do not write the main method. 
    int l1=length(headA);
    int l2=length(headB);
    Node* temp1;
    Node* temp2;
    if(l1==l2)
        temp1=headA, temp2=headB;
    else if(l1>l2)
        temp1=position(headA, l1-l2), temp2=headB;
    else
        temp1=headA, temp2=position(headB, l2-l1);
    
    return common(temp1, temp2);
}