As the linked list is sorted, we can start from the beginning of the list and compare adjacent nodes. When adjacent nodes are the same, remove the second one. There’s a tricky case where the node after the next node needs to be noted before the deletion.

// Remove duplicates from a sorted list

void RemoveDuplicates(struct node* head)

{

struct node* current = head;

if (current == NULL) return; // do nothing if the list is empty

// Compare current node with next node

while(current->next!=NULL)

{

if (current->data == current->next->data)

{

struct node* nextNext = current->next->next;

free(current->next);

current->next = nextNext;

}

else

{

current = current->next; // only advance if no deletion

}

}

}

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