Thread: Linked List

Hello!
I am trying hard to follow the Linked List concept.
I was trying to work towards the adjacent list. I am using the function to make adjacent list but am not able to pass my data to it.
Can someone help me with this?
the code is

Code:

struct adj_node  /*the NODE which forms the part of the adjacency list; look at figure [B]*/
{
char vertex_val;
struct adj_node *adj_next; /*red pointer*/
};

struct node /*the NODE which forms the part of the Graph; look at figure [A]*/
{
char vertex_val;
struct adj_node *down;
struct node *next;  /*black pointer*/
};

struct node *graph; 
struct node *cur_vertex, *aux_ptr;
struct adj_node *adj_cur, *new;

LinkListrepresentation()
{


/*Step-1 of the algorithm is expected from you or refer linked LISTS*/ 
/*Step-1 gives you a list, being pointed by 'graph' */ 

cur_vertex = graph;   /*first node of the graph in consideration*/
/*Step-2 starts here*/
while ( cur_vertex != NULL)
      {
       aux_ptr = graph; /*an auxiliary pointer to the graph*/
       adj_cur = NULL; /*an auxiliary pointer to keep track of the adjacency lists*/
       cur_vertex->down = adj_cur; 
       while (aux_ptr != NULL)
             {
              printf("Is there any edge between %c and %c ",aux_ptr->vertex_val, cur_vertex->vertex_val);
              scanf("%d", &edge);/*step-2: part-A*/
              if( edge == 1) /*step-2: part - B*/
                 if( adj_cur == NULL)
                   {
                    adj_cur = (struct adj_node *)malloc(sizeof(adj_node));
                    adj_cur ->vertex_val = aux_ptr->vertex_val;
                    adj_cur -> adj_next = NULL;
                   } 
                  else
                   {
                     new = (struct adj_node *)malloc(sizeof(adj_node));
                     new -> vertex_val = aux_ptr ->vertex_val;
                     adj_cur ->adj_next = new;
                     adj_cur = new; 
                     adj_cur ->adj_next = NULL;
                   }  
               aux_ptr = aux_ptr ->next;
             }
        cur_vertex = cur_vertex ->next;
     }
}

I want to pass the data to the above function for making the LL but i dont know how it shd be passed.
I am reading the data from the file as

Code:

FILE *fp;
  int i, count = 0;
  char c;
  
  fp = fopen("data","r");    // reading the Edge file
  while((c=getc(fp))!=EOF) 
    {
      if(c=='\n')
	count++;
    }
  printf("\tThe total number of entries: %d\n", count);   
  C1 = (int*) calloc(edges, sizeof(int));
  C2 = (int*) calloc(edges, sizeof(int));
  C3 = (float*) calloc(edges, sizeof(float));
  rewind(fp2);
  for (i=0;i<edges;i++)
    {
      fscanf(fp,"%d  %d %f \n", &C1[i], &C2[i], &C3[i]);
      //   printf("%d  %d %f  %c\n", C1[i], C2[i], pC3[i], C4[i]);   
      
	}

Is that all of the code? Sure doesn't seem like it. Most of your used variables are undeclared. And passing the root node to your function should be enough, checking for node->next != NULL

Code:

while(node){
    ...
    node = node->next
}

I am reading my file in 3 columns. C1, C2, C3.
I dont know how to put that in LL.
C1 = Node1
C2 = Node2
C3 = Value.

it didnt work out for me
I couldn't pass the input file to the above mentioned structure.
Am I reading my data in some wrong format ????