src/test/dijkstra_heap_test.cc
author jacint
Fri, 23 Apr 2004 18:48:56 +0000
changeset 384 f27d21767d38
child 386 0bdc7c279e79
permissions -rw-r--r--
Testfile for dijkstra.h, bin_heap.h and fib_heap.h
     1 //Tests dijsktra.h with two heap implementations:
     2 //the default binary heap of bin_heap.h, and the 
     3 //Fibonacci heap of fib_heap.h.
     4 
     5 //The input is a graph in standard dimacs format from the standard input (like
     6 //in /hugo_loc/testfiles/dimacs). It runs dijkstra.h on this graph with
     7 //both heaps, checking two postconditions: 
     8 
     9 //- if the edges e=uv of the shortest path tree reported by dijkstra.h have
    10 //dist(v)-dist(u)=length(e)
    11 
    12 // - if all edges e=uv with u reachable from the root have
    13 //dist(v)-dist(u)>=length(e)
    14 #include <iostream>
    15 #include <math.h>
    16 
    17 #include <smart_graph.h>
    18 #include <dimacs.h>
    19 #include <dijkstra.h>
    20 #include <time_measure.h>
    21 #include <bin_heap.h>
    22 #include <for_each_macros.h>
    23 
    24 using namespace hugo;
    25 
    26 int main(int, char **) {
    27   
    28   typedef SmartGraph Graph;
    29 
    30   typedef Graph::Edge Edge;
    31   typedef Graph::Node Node;
    32   typedef Graph::EdgeIt EdgeIt;
    33   typedef Graph::NodeIt NodeIt;
    34   typedef Graph::EdgeMap<int> LengthMap;
    35 
    36   Graph G;
    37   Node s, t;
    38   LengthMap cap(G);
    39   readDimacsMaxFlow(std::cin, G, s, t, cap);
    40   Timer ts;
    41     
    42   std::cout <<
    43     "\n  Testing dijkstra.h with binary heap implementation bin_heap.h,"
    44 	    <<std::endl;
    45   std::cout<<"  on a graph with " << 
    46     G.nodeNum() << " nodes and " << G.edgeNum() << " edges..."
    47 	   << std::endl<<std::endl;
    48   
    49   Dijkstra<Graph, LengthMap> 
    50     dijkstra_test(G, cap);
    51   ts.reset();
    52   dijkstra_test.run(s);
    53   std::cout << "elapsed time: " << ts << std::endl;
    54   
    55   int error1=0;
    56   int error2=0;
    57 
    58   FOR_EACH_LOC ( EdgeIt, e, G) {
    59     Node u=G.tail(e);
    60     Node v=G.head(e);
    61     if ( dijkstra_test.dist(v) - dijkstra_test.dist(u) > cap[e] )
    62       if ( dijkstra_test.reached(u) ) {
    63 	std::cout<<"Error! dist(head)-dist(tail)- edge_length= " 
    64 		 <<dijkstra_test.dist(v) - dijkstra_test.dist(u) 
    65 	  - cap[e]<<std::endl;
    66 	++error1;
    67       }
    68   }
    69 
    70   FOR_EACH_LOC ( NodeIt, v, G) {
    71     if ( dijkstra_test.reached(v) ) {
    72       Edge e=dijkstra_test.pred(v);
    73       Node u=G.tail(e);
    74       if ( dijkstra_test.dist(v) - dijkstra_test.dist(u) != cap[e] ) {
    75 	std::cout<<"Error in a shortest path tree edge! Difference: " 
    76 		 <<std::abs(dijkstra_test.dist(v) - dijkstra_test.dist(u) 
    77 			    - cap[e])<<std::endl;
    78 	++error2;
    79       }
    80     }
    81   }
    82 
    83 
    84   
    85   std::cout << error1 << " non-tree and " << error2 
    86 	    << " shortest path tree edge is erroneous."<<std::endl;
    87 
    88 
    89 
    90   std::cout <<
    91     "\n  Testing dijkstra.h with Fibonacci heap implementation fib_heap.h,"
    92 	    <<std::endl;
    93   std::cout<<"  on a graph with " << 
    94     G.nodeNum() << " nodes and " << G.edgeNum() << " edges..."
    95 	   << std::endl<<std::endl;
    96   
    97   Dijkstra<Graph, LengthMap, FibHeap> 
    98     dijkstra_test2(G, cap);
    99   ts.reset();
   100   dijkstra_test2.run(s);
   101   std::cout << "elapsed time: " << ts << std::endl;
   102   
   103   error1=0;
   104   error2=0;
   105 
   106   FOR_EACH_LOC ( EdgeIt, e, G) {
   107     Node u=G.tail(e);
   108     Node v=G.head(e);
   109     if ( dijkstra_test2.dist(v) - dijkstra_test2.dist(u) > cap[e] )
   110       if ( dijkstra_test2.reached(u) ) {
   111 	std::cout<<"Error! dist(head)-dist(tail)- edge_length= " 
   112 		 <<dijkstra_test2.dist(v) - dijkstra_test2.dist(u) 
   113 	  - cap[e]<<std::endl;
   114 	++error1;
   115       }
   116   }
   117 
   118   FOR_EACH_LOC ( NodeIt, v, G) {
   119     if ( dijkstra_test2.reached(v) ) {
   120       Edge e=dijkstra_test2.pred(v);
   121       Node u=G.tail(e);
   122       if ( dijkstra_test2.dist(v) - dijkstra_test2.dist(u) != cap[e] ) {
   123 	std::cout<<"Error in a shortest path tree edge! Difference: " 
   124 		 <<std::abs(dijkstra_test2.dist(v) - dijkstra_test2.dist(u) 
   125 			    - cap[e])<<std::endl;
   126 	++error2;
   127       }
   128     }
   129   }
   130 
   131 
   132   std::cout << error1 << " non-tree and " << error2 
   133 	    << " shortest path tree edge is erroneous."<<std::endl;
   134 
   135 
   136   return 0;
   137 }