Can we delete the last node of a Single Linked list if we only know the address of last node

Question

// Variables

typedef struct node 
 { 
    int value; 
    struct node *next; 
 }mynode;

// Globals (not required, though).

mynode *head, *tail, *temp; 

// Functions

void add(int value);

// Function to add new nodes to the linked list

 void add(int value)
 {
    temp = (mynode *) malloc(sizeof(struct node));
    temp->next=(mynode *)0;
    temp->value=value;

    if(head==(mynode *)0)
    {
       head=temp;
       tail=temp;
    }
    else
    {
      tail->next=temp;
      tail=temp;
    }
 }

// The main() function

int main()
 {
     head=(mynode *)0;

     // Construct the linked list.
     add(1);
     add(2);
     add(3);

     return(0);
 }

If I only have a pointer to a node, whose value is 3(The Last node as seen in the aforementioned code) , Can we delete it and make a node whose value is 2(aforementioned code) as the last node.

Answer 1

No you can not. Unless you have some reference to previous node. like head pointer. If you have other reference than its pretty much easier. In fact if you don't have any pointers you will loose the list itself