Version 5.0 The LEDA User Manual

• Opposite Graphs (opposite graph) are a variant of the bidirectional graph category.
They do not support the computation of the source or target node of a given edge
but allow to walk from one terminal v of an edge e to the other opposite one.
Not yet implemented are bidirected and undirected graph.
1.4 Node and Edge Data. Static graph support several efficient ways - efficient compared
to using node arrays, edge arrays, node maps, and edge maps - to associate data
with the edges and nodes of the graph.
1.4.1 Dynamic Slot Assignment: It is possible to attach two optional template parameters
data slots at compile time:
static_graph G;
specifies a static directed graph G with three additional node slots and one additional
edge slot. Node and edge arrays can use these data slots, instead of allocating an external
array. This method is also supported for the standard LEDA data type graph. Please see
the manual page for node array resp. edge array (esp. the operations use node data resp.
use edge data) for the details.
The method is called dynamic slot assignment since the concrete arrays are assigned
during runtime to the slots.
1.4.2 Static Slot Assignment: This method is even more efficient. A variant of the
node and edge arrays, the so-called node slot and edge slot data types, are assigned to
the slots during compilation time. These types take three parameters: the element type
of the array, an integer slot number, and the type of the graph:
node_slot;
edge_slot;
Here is an example for the use of static slot assignment in a maxflow graph algorithm.
It uses three node slots for storing distance, excess, and a successor node, and two edge
slots for storing the flow and capacity.
typedef static_graph maxflow_graph;
node_slot succ;
node_slot dist;
node_slot excess;
edge_slot flow;
edge_slot cap;