All paths between two nodes in a directed graph

To find all possible paths between two nodes in a directed acyclic graph :

'path' is a list or array.

Add source_node to path ;

find_nodes ( source_node , path ) ;

find_nodes ( my_node , path )
{
if ( my_node == destination_node )
{
print path ;
return ;
}
Find all the possible nodes that are reachable directly
from my_node ;
For each such new_node found
{
Add this new_node to path ;
find_nodes ( new_node , path ) ;
Remove this new_node from path ;
}
return ;
}

This uses a technique called recursion. You might have heard that to iterate is human but to recurse, is divine.