PROG2

/////////////////MAIN_CORR.C///////////////////


#include <stdio.h>
#include "fgraph.h"

void print_fgraph(struct fgraph *G);

int main(int argc, char *argv[]) {
	struct fgraph *G;

	if(argc != 2) {
		fprintf(stderr,"Usage: fgraph <file>\n");
		return 1;
	}
	if((G = read_fgraph(argv[1])) == NULL) {
		fprintf(stderr,"Error reading %s\n",argv[1]);
		return 1;

	}

	print_fgraph(G);
	system("PAUSE");
	return 0;
}
/////////////////////////////////////////////////////


///////////////////////FGRAPH:C///////////////////////////////
#include <stdio.h>
#include <stdlib.h>
#include "fgraph.h"

#define N 1000

struct fgraph *read_fgraph(char *filename) {
  FILE *in = fopen(filename,"r");
  struct fgraph *G = NULL;
  unsigned int i, n, m;

  if(in != NULL && fscanf(in,"%u %u\n",&n,&m) != EOF) {
    unsigned int id, id1, id2;
    char name[N];

    for(i = 0; i < n && fscanf(in,"%u",&id) != EOF &&  fgets(name,N,in) != NULL; i++) {
      name[strlen(name)-1]='\0';
      insert_individual(&G,strcpy(calloc(strlen(name)+1,sizeof(char)),name),id);
    }

    for(i = 0; i < m && fscanf(in,"%u %u",&id1,&id2) != EOF; i++)
      insert_friendship(G,id1,id2);

    fclose(in);
  }

  return G;
}

static struct fgraph * individual_alloc(char *name, unsigned int id)
{
	struct fgraph *tmp = (struct fgraph *)calloc(1, sizeof(struct fgraph));

	if (tmp != NULL) {
		tmp->friends = NULL;
		tmp->id = id;
		tmp->name = name;
		tmp->next = NULL;
		tmp->prev = NULL;
	}
	return tmp;
}

static struct list * friend_alloc(unsigned int id)
{
	struct list *tmp = (struct list *)calloc(1, sizeof(struct list));

	if (tmp != NULL) {
		tmp->id = id;
		tmp->next = NULL;
		tmp->prev = NULL;
	}
	return tmp;
}


static int in_inlist(struct fgraph **G, unsigned int id)
{
	if ((G == NULL) || (*G == NULL)) {
		return 0;
	}
	else {
		struct fgraph *tmp = *G;
		while (tmp != NULL && tmp->id != id)
			tmp = tmp->next;
		return tmp != NULL;
	}
}

static int in_inlist_friend(struct fgraph *G, unsigned int id)
{
		struct list *tmp = (*G).friends;
		while (tmp != NULL && tmp->id != id)
			tmp = tmp->next;
		return tmp != NULL;
}

static struct list * body_search(struct fgraph *G, unsigned int id) {
	while (id != G->id && G != NULL)
		G = G->next;
	return G;

}
int insert_individual(struct fgraph **G, char *name, unsigned int id) {

	struct fgraph *tmp = individual_alloc(name, id);

	if ((G == NULL) || (*G == NULL))
	{
		*G = tmp;
		return *G == NULL;
	}
	else
	{
		if (!in_inlist(&(*G), id))
		{
			if (tmp != NULL) {
				tmp->next = *G;
				(*G)->prev = tmp;
				*G = tmp;
			}
			return tmp == NULL;
		}
		else
			return 0;
	}
}

int insert_friendship(struct fgraph *G, unsigned int id1, unsigned int id2) {

	if (in_inlist(&G, id1) && in_inlist(&G, id2))
	{
		if (!in_inlist_friend(G, id1) || !in_inlist_friend(G, id2))
		{
			struct fgraph *p1 = body_search(G, id1);
			struct fgraph *p2 = body_search(G, id2);
			struct list *tmp1 = friend_alloc(id1);
			struct list *tmp2 = friend_alloc(id2);

			if (p1->friends == NULL)
				p1->friends = tmp2;
			else
			{
				//p to p per scorrere la lista
				struct list *ciclo1 = (*p1).friends;
				while (ciclo1->next != NULL)
					ciclo1 = ciclo1->next;

				ciclo1->next = tmp2;
				(ciclo1->next)->prev = ciclo1;
			}



			if (p2->friends == NULL)
				p2->friends = tmp1;
			else
			{
				//p to p per scorrere la lista
				struct list *ciclo2 = (*p2).friends;
				while (ciclo2->next != NULL)
					ciclo2 = ciclo2->next;

				ciclo2->next = tmp1;
				(ciclo2->next)->prev = ciclo2;
			}
			return 0;
		}
		else
			return 0;

	}

	return 1;
}
//////////////////END//////////////////////
////////////////////////FGRAPH:H/////////////////////
#ifndef FGRAPH_H
#define FGRAPH_H

struct list {
	unsigned int id;
	struct list *next;
	struct list *prev;
};

struct fgraph {
	char *name;
	unsigned int id;
	struct list *friends;
	struct fgraph *next;
	struct fgraph *prev;
};

struct fgraph *read_fgraph(char *filename);

int insert_individual(struct fgraph **G, char *name, unsigned int id);

int insert_friendship(struct fgraph *G, unsigned int id1, unsigned int id2);



#endif
////////////////////////END////////////////////////