Hong Quan - Graph

#include "stdio.h"
#include "conio.h"
#include "malloc.h"
#define MAX 100

struct node
{
    int key;
    struct node *next;
};

struct node *a[MAX];
struct node *z;

int val[MAX];
int n;
int id = 0;

void init(int r)
{
    int i;

    z =(struct node *) malloc(sizeof *z);
    z->key = -1;
    z->next = z;

    for(i = 1; i <= r; ++i)
    {
        a[i] =(struct node *) malloc(sizeof *a[i]);
        a[i]->key = -1;
        a[i]->next = z;
    }
}

int index(char c)
{
    int t;
    t = c - 'A' + 1;
    return t;
}

void show(struct node *t)
{
    struct node *k;
    k = t->next;
    while(k != z)
    {
        printf("%3d", k->key);
        k = k->next;
    }
}

void insert(int x, struct node *q, struct node *k)
{
    struct node *p;

    q->key = x;
    q->next = z;
    p = k;

    if(p->next == z)
    {
        k->next = q;
    }
    else
    {
        while(p->next != z)
        {
            p = p->next;
        }
        p->next= q;
    }
}

void vist(int k)
{
    struct node *t;
    val[k] = ++id;
    //printf("\n Tada %d", val[k]);
    printf("\n\nVisited vertex %d", k);
    for(t = a[k]->next; t!= z; t = t->next)
    {
        if(val[t->key] == 0)
            vist(t->key);
    }
}

void listdfs()
{
    int i;
    for(i = 1; i <= n; ++i)
    {
        val[i] = 0;
    }
    for(i = 1; i <= n; ++i)
    {
        if(val[i] == 0) vist(i);
    }
}

void del_node(int x, int y)
{
    struct node *t;
    struct node *k;
    struct node *m;

    k = a[y];
    t = a[x];

    if(k->key == x)
    {
        m = k;
        k = k->next;
        free(m);
    }
    else
    {
        while(k->next->key != x)
        {
            k = k->next;
            if(k->next == z)
            {
                printf("\nThere is no edge between %d and %d", x, y);
                goto tt;
            }
        }
        m = k->next;
        k->next = k->next->next;
        free(m);
    }

    if(t->key == y)
    {
        m = t;
        t = t->next;
        free(m);
    }
    else
    {
        while(t->next->key != y)
        {
            t = t->next;
        }
        m = t->next;
        t->next = t->next->next;
        free(m);
    }
    tt:;
}

void sort(int i)
{
    struct node *t;
    int ks[MAX];
    int d = 0;
    int j, r, q;

    for(t = a[i]; t != z; t = t->next)
    {
        d += 1;
        ks[d] = t->key;
    }

    for(j = 1; j <= d; ++j)
    {
        for(r = j + 1; r <= d; ++r)
        {
            if(ks[j] > ks[r])
            {
                q = ks[r];
                ks[r] = ks[j];
                ks[j] = q;
            }
        }
    }

    d = 0;
    for(t = a[i]; t != z; t = t->next)
    {
        d += 1;
        t->key = ks[d];
    }
}

int main()
{
    struct node *q;
    int x, i, stop;
    FILE *fp;

    //open file
    fp = fopen("alo.txt", "r");
    if(fp == NULL)
    {
        printf("\nError");
        return 0;
    }

    //scan n
    fscanf(fp, "%d\n", &n);
    printf("\n\nGraph G has: %d vertexes", n);
    init(n);

    //...
    while(!feof(fp))
    {
        fscanf(fp, "%d\n", &i);
        stop = 0;
        while(!stop)
        {
            fscanf(fp, "%d\n", &x);
            if(x != 0)
            {
                q =(struct node *) malloc(sizeof *q);
                insert(x, q, a[i]);
            }
            else stop = 1;
        }
    }

    //close file
    fclose(fp);

    //del sth
    del_node(1, 2);
    del_node(1, 3);
    del_node(5, 4);

    //sort sth
    /*for(i = 1; i <= n; ++i)
    {
        sort(i);
    }*/

    //print
    for(i = 1; i <= n; ++i)
    {
        printf("\n\tVertex %d:", i);
        show(a[i]);
    }

    printf("\n\nStarting visit :");
    listdfs();

    printf("\n\n");
    getch();
}