Given two linked lists, insert nodes of second list into first list at alternate positions of first list.
void merge[struct node *p,struct node **q]
{
struct node *p_curr = p, *q_curr = *q;
struct node *p_next, *q_next;
// While therre are avialable positions in p
while [p_curr != NULL && q_curr != NULL]
{
// Save next pointers
p_next = p_curr->next;
q_next = q_curr->next;
// Make q_curr as next of p_curr
q_curr->next = p_next;// Change next pointer of q_curr
p_curr->next = q_curr;// Change next pointer of p_curr
// Update current pointers for next iteration
p_curr = p_next;
q_curr = q_next;
}
*q = q_curr;// Update head pointer of second list
}
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