src/work/jacint/graph_gen.h
changeset 553 8e5102790d4d
child 558 4cbfb435ec2b
equal deleted inserted replaced
-1:000000000000 0:cafdab7fce71
       
     1 // -*- c++ -*-
       
     2 //randomGraph(i,j) gives a random graph on i nodes and j edges.
       
     3 #include <vector>
       
     4 #include <cstdlib>
       
     5 
       
     6 //#include <list_graph.h>
       
     7 //#include <time_measure.h>
       
     8 //#include <for_each_macros.h>
       
     9 //#include <bfs_iterator.h>
       
    10 //#include <bipartite_graph_wrapper.h>
       
    11 //#include <maps.h>
       
    12 //#include <max_flow.h>
       
    13 
       
    14 namespace hugo {
       
    15 
       
    16 
       
    17   /**
       
    18    * Inicializalja a veletlenszamgeneratort.
       
    19    * Figyelem, ez nem jo igazi random szamokhoz,
       
    20    * erre ne bizzad a titkaidat!
       
    21    */
       
    22   void random_init()
       
    23   {
       
    24     unsigned int seed = getpid();
       
    25     seed |= seed << 15;
       
    26     seed ^= time(0);
       
    27 
       
    28     srand(seed);
       
    29   }
       
    30 
       
    31 
       
    32   /**
       
    33    * Egy veletlen int-et ad vissza 0 es m-1 kozott.
       
    34    */
       
    35   int random(int m)
       
    36   {
       
    37     return int( double(m) * rand() / (RAND_MAX + 1.0) );
       
    38   }
       
    39 
       
    40 
       
    41   template<typename Graph>
       
    42   void randomGraph (Graph& g, int n, int m) {
       
    43     typedef typename Graph::Node Node;
       
    44     g.clear();
       
    45     std::vector<Node> nodes;
       
    46     for (int i=0; i<n; ++i)
       
    47       nodes.push_back(g.addNode());
       
    48     for (int i=0; i<m; ++i) 
       
    49       g.addEdge(nodes[random(n)], nodes[random(n)]);
       
    50   }
       
    51 
       
    52 }