please help me. i am not getting display of graph properly.

/*graph.h*/

#ifndef GRAPH_H
#define GRAPH_H

#include <stdlib.h>

#include "list.h"
#include "set.h"

typedef struct AdjList_ {

void *vertex;
Set adjacent;

} AdjList;

typedef struct Graph_ {

int vcount;
int ecount;

int (*match)(const void *key1, const void *key2);
void (*destroy)(void *data);

List adjlists;

} Graph;

typedef enum VertexColor_ {white, gray, black} VertexColor;

void graph_init(Graph *graph, int(*match)(const void *key1, const void *key2), void (*destroy)(void *data));

void graph_destroy(Graph *graph);

int graph_ins_vertex(Graph *graph, const void *data);

int graph_ins_edge(Graph *graph, const void *data1, const void *data2);

int graph_rem_vertex(Graph *graph, void **data);

int graph_rem_edge(Graph *graph, void *data1, void **data2);

int graph_adjlist(const Graph *graph, const void *data, AdjList **adjlist);

int graph_is_adjacent(const Graph *graph, const void *data1, const void *data2);

#define graph_adjlists(graph) ((graph)->adjlists)

#define graph_vcount(graph) ((graph)->vcount)

#define graph_ecount(graph) ((graph)->ecount)

#endif

/*graph.c*/

#include <stdlib.h>
#include <string.h>

#include "graph.h"
#include "list.c"
#include "set.c"

void graph_init(Graph *graph, int(*match)(const void *key1, const void *key2), void (*destroy)(void *data)) {

graph->vcount = 0;
graph->ecount = 0;
graph->match = match;
graph->destroy = destroy;

list_init(&graph->adjlists, NULL);

return;

}

void graph_destroy(Graph *graph) {

AdjList *adjlist;

while (list_size(&graph->adjlists) > 0) {

if (list_rem_next(&graph->adjlists, NULL, (void**)&adjlist) == 0) {

set_destroy(&adjlist->adjacent);

if (graph->destroy != NULL)
graph->destroy(adjlist->vertex);

free(adjlist);

}

}

list_destroy(&graph->adjlists);

memset(graph, 0, sizeof(Graph));

return;

}

int graph_ins_vertex(Graph *graph, const void *data) {

ListElmt *element;

AdjList *adjlist;

int retval;

for(element = list_head(&graph->adjlists); element != NULL; element = list_next(element)) {

if(graph->match(data, ((AdjList *)list_data(element))->vertex))
return 1;

}

if ((adjlist = (AdjList *)malloc(sizeof(AdjList))) == NULL)
return -1;

adjlist->vertex = (void *)data;
set_init(&adjlist->adjacent, graph->match, NULL);

if ((retval = list_ins_next(&graph->adjlists, list_tail(&graph->adjlists), adjlist)) != 0) {

return retval;

}

graph->vcount++;

return 0;

}

/*implementation of graphs*/

#include "graph.c"


int data_match (void *key1, void *key2)
{

if(key1 == key2)
return 1;

else
return 0;

}

int list_display(List *list)
{

ListElmt *element;

printf("\nThe vertices in the graph are : ");
for(element = list_head(list); element != NULL; element = list_next(element))
printf("%d ", list_data(element));

}

int main()
{

int choice, num, sour, dest, flag = 0;
Graph *graph;

printf("\n\n\n*****IMPLEMENTATION OF GRAPHS***\n");

start: printf("\n1. Initialize a graph");
printf("\n2. Insert a vertex in the graph");
printf("\n3. Insert an edge in the graph");
printf("\n4. Delete a vertex from the graph");
printf("\n5. Delete an edge from the graph");
printf("\n6. Display the graph");
printf("\n7. Destroy the graph");
printf("\n8. Exit");
printf("\n Enter your choice : ");

choice: scanf("%d", &choice);

if(choice == 8)
return -1;

if (choice > 8)
{
printf("No such choice. Enter choice again : ");
goto choice;
}

if(choice != 1 && flag == 0)
{
printf("Unless a graph is created, this operation is invalid.\n");
goto start;
}

switch(choice)
{

case 1:

if (flag == 1)
{
printf("\nA graph is in use. Destroy it before initialing a new graph.\n");
goto start;
}

graph = malloc(sizeof(Graph));
graph_init(graph, data_match, NULL);

printf("\nThe graph is initialized.\n");

flag = 1;

goto start;

case 2:

printf("\nEnter the vertex to be inserted in the graph : ");
scanf("%d", &num);

if (graph_ins_vertex(graph, num) == 1)
printf("The vertex already exists.\n");
else
printf("The new vertex is inserted in the graph.\n");

goto start;

case 3:

printf("\nEnter the source vertex : ");
scanf("%d", &sour);

printf("Enter the terminating vertex : ");
scanf("%d", &dest);

if (graph_ins_edge(graph, sour, dest) == -1)
printf("Either one of the vertices may be wrong or the edge already exists.\n");
else
printf("The new edge is inserted in the graph.\n");

goto start;

case 4:

printf("\nEnter the vertex to be removed : ");
scanf("%d", &num);

if (graph_rem_vertex(graph, &num) == 0)
printf("The vertex is removed.\n");
else
printf("Either edges incident to/from the vertex may not be deleted or it is not present.\n");

if (graph->vcount == 0)
{
flag = 0;
printf("The graph is empty. The graph is destroyed.\n");
graph_destroy(graph);
}

goto start;

case 5:

printf("\nEnter the source vertex of the edge to be removed : ");
scanf("%d", &sour);

printf("Enter the terminating vertex of the edge to be removed : ");
scanf("%d", &dest);

if (graph_rem_edge(graph, sour, &dest) == 0)
printf("The edge is removed.\n");
else
printf("Either one of the vertices may be wrong or the edge does not exist.\n");

goto start;

case 6:

printf("\nThe graph is decribed as follows :");
list_display(&graph_adjlists(graph));

goto start;

case 7:

graph_destroy(graph);
printf("\nThe graph is destroyed.\n");

flag = 0;

goto start;


}

}

int graph_ins_edge(Graph *graph, const void *data1, const void *data2) {

ListElmt *element;

int retval;

for (element = list_head(&graph->adjlists); element != NULL; element = list_next(element)) {

if(graph->match(data2, ((AdjList *)list_data(element))->vertex))
break;

}

if (element == NULL)
return -1;

for (element = list_head(&graph->adjlists); element != NULL; element = list_next(element)) {

if(graph->match(data1, ((AdjList *)list_data(element))->vertex))
break;

}

if (element == NULL)
return -1;

if ((retval = set_insert(&((AdjList *)list_data(element))->adjacent, data2)) != 0) {

return retval;

}

graph->ecount++;

return 0;

}

int graph_rem_vertex(Graph *graph, void **data) {

ListElmt *element,
*temp,
*prev;

AdjList *adjlist;

int found;

prev = NULL;
found = 0;

for (element = list_head(&graph->adjlists); element != NULL; element = list_next(element)) {

if (set_is_member(&((AdjList *)list_data(element))->adjacent, *data))
return -1;

if (graph->match(*data, ((AdjList *)list_data(element))->vertex)) {

temp = element;
found = 1;

}

if (!found)
prev = element;

}

if(!found)
return -1;

if(set_size(&((AdjList *)list_data(temp))->adjacent) > 0)
return -1;

if (list_rem_next(&graph->adjlists, prev, (void **)&adjlist) != 0)
return -1;

*data = adjlist->vertex;
free(adjlist);

graph->vcount--;

return 0;

}

int graph_rem_edge(Graph *graph, void *data1, void **data2) {

ListElmt *element;

for (element = list_head(&graph->adjlists); element != NULL; element = list_next(element)) {

if (graph->match(data1, ((AdjList *)list_data(element))->vertex))
break;

}

if (element ==NULL)
return -1;

if(set_remove(&((AdjList *)list_data(element))->adjacent, data2) != 0)
return -1;

graph->ecount--;

return 0;

}

int graph_adjlist(const Graph *graph, const void *data, AdjList **adjlist) {

ListElmt *element,
*prev;

prev = NULL;

for (element = list_head(&graph->adjlists); element != NULL; element = list_next(element)) {

if (graph->match(data, ((AdjList *)list_data(element))->vertex))
break;

prev = element;

}

if (element == NULL)
return -1;

*adjlist = list_data(element);

return 0;

}

int graph_is_adjacent(const Graph *graph, const void *data1, const void *data2) {

ListElmt *element,
*prev;

prev = NULL;

for (element = list_head(&graph->adjlists); element != NULL; element = list_next(element)) {

if (graph->match(data1, ((AdjList *)list_data(element))->vertex))
break;

prev = element;

}

if (element == NULL)
return 0;

return set_is_member(&((AdjList *)list_data(element))->adjacent, data2);

}

please help me solve to solve the problem of displaying a graph in the program i sent as implementing a graph