Q. Write down the algorithm which does depth first search through an un-weighted connected graph. In an un-weighted graph, would breadth first search or depth first search or neither find a shortest path tree from some of the node? Why?                                                                                     

Ans:

An algorithm that does depth first search is written below:

struct node

{

int data ;

struct node *next ;

} ; int visited[MAX] ;

void dfs ( int v, struct node **p )

{

struct node *q ;

visited[v - 1] = TRUE ;

printf ( "%d\t", v ) ; q = * ( p + v - 1 ) ; while ( q != NULL )

{

if ( visited[q -> data - 1] == FALSE )

dfs ( q -> data, p ) ;

else 

q = q -> next ;}

}