depth first search algorithm.

depth first search algorithm.

#include "stdio.h"
#include "conio.h"
#include "alloc.h"

#define TRUE 1
#define FALSE 0
#define MAX 8

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

int visited[MAX] ;

void dfs ( int, struct node ** ) ;
struct node * getnode_write ( int ) ;
void del ( struct node * ) ;

void main( )
{
struct node *arr[MAX] ;
struct node *v1, *v2, *v3, *v4 ;
int i ;

clrscr( ) ;

v1 = getnode_write ( 2 ) ;
arr[0] = v1 ;
v1 -> next = v2 = getnode_write ( 3 ) ;
v2 -> next = NULL ;

v1 = getnode_write ( 1 ) ;
arr[1] = v1 ;
v1 -> next = v2 = getnode_write ( 4 ) ;
v2 -> next = v3 = getnode_write ( 5 ) ;
v3 -> next = NULL ;

v1 = getnode_write ( 1 ) ;
arr[2] = v1 ;
v1 -> next = v2 = getnode_write ( 6 ) ;
v2 -> next = v3 = getnode_write ( 7 ) ;
v3 -> next = NULL ;

v1 = getnode_write ( 2 ) ;
arr[3] = v1 ;
v1 -> next = v2 = getnode_write ( 8 ) ;
v2 -> next = NULL ;

v1 = getnode_write ( 2 ) ;
arr[4] = v1 ;
v1 -> next = v2 = getnode_write ( 8 ) ;
v2 -> next = NULL ;

v1 = getnode_write ( 3 ) ;
arr[5] = v1 ;
v1 -> next = v2 = getnode_write ( 8 ) ;
v2 -> next = NULL ;

v1 = getnode_write ( 3 ) ;
arr[6] = v1 ;
v1 -> next = v2 = getnode_write ( 8 ) ;
v2 -> next = NULL ;

v1 = getnode_write ( 4 ) ;
arr[7] = v1 ;
v1 -> next = v2 = getnode_write ( 5 ) ;
v2 -> next = v3 = getnode_write ( 6 ) ;
v3 -> next = v4 = getnode_write ( 7 ) ;
v4 -> next = NULL ;

dfs ( 1, arr ) ;

for ( i = 0 ; i < q =" *"> data - 1] == FALSE )
dfs ( q -> data, p ) ;
else
q = q -> next ;
}
}

struct node * getnode_write ( int val )
{
struct node *newnode ;
newnode = ( struct node * ) malloc ( sizeof ( struct node ) ) ;
newnode -> data = val ;
return newnode ;
}

void del ( struct node *n )
{
struct node *temp ;

while ( n != NULL )
{
temp = n -> next ;
free ( n ) ;
n = temp ;
}
}