Definition
An instance of the data type node_map2<E> is a map2 for the pairs of nodes of a graph G, i.e., equivalent to map2 < node, node, E > (cf. Two-Dimensional Maps). It can be used as a dynamic variant of the data type nodematrix (cf. Two Dimensional Node Arrays).
#include < LEDA/graph/node_map2.h >
Creation
node_map2<E> | M | introduces a variable M of type node_map2<E> and initializes it to the map2 with empty domain. |
node_map2<E> | M(const graph_t& G) | introduces a variable M of type node_map2<E> and initializes it with a mapping m from the set of all nodes of G into the set of variables of type E. The variables in the range of m are initialized by a call of the default constructor of type E. |
node_map2<E> | M(const graph_t& G, E x) | introduces a variable M of type node_map2<E> and initializes it with a mapping m from the set of all nodes of G into the set of variables of type E. The variables in the range of m are initialized with a copy of x. |
Operations
Implementation
Node maps are implemented by an efficient hashing method based on the internal numbering of the nodes. An access operation takes expected time O(1).