[384] | 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 |
---|
[422] | 6 | //in /hugo_loc/testfiles/dimacs). It runs dijkstra.h on this graph with both |
---|
| 7 | //heaps, checking two postconditions: |
---|
[384] | 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> |
---|
[386] | 22 | #include <fib_heap.h> |
---|
[384] | 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 | |
---|
[449] | 58 | EdgeIt e; |
---|
| 59 | for(G.first(e); G.valid(e); G.next(e)) { |
---|
[384] | 60 | Node u=G.tail(e); |
---|
| 61 | Node v=G.head(e); |
---|
| 62 | if ( dijkstra_test.dist(v) - dijkstra_test.dist(u) > cap[e] ) |
---|
| 63 | if ( dijkstra_test.reached(u) ) { |
---|
| 64 | std::cout<<"Error! dist(head)-dist(tail)- edge_length= " |
---|
| 65 | <<dijkstra_test.dist(v) - dijkstra_test.dist(u) |
---|
| 66 | - cap[e]<<std::endl; |
---|
| 67 | ++error1; |
---|
| 68 | } |
---|
| 69 | } |
---|
| 70 | |
---|
[449] | 71 | NodeIt v; |
---|
| 72 | for(G.first(v); G.valid(v); G.next(v)) { |
---|
[384] | 73 | if ( dijkstra_test.reached(v) ) { |
---|
| 74 | Edge e=dijkstra_test.pred(v); |
---|
| 75 | Node u=G.tail(e); |
---|
| 76 | if ( dijkstra_test.dist(v) - dijkstra_test.dist(u) != cap[e] ) { |
---|
| 77 | std::cout<<"Error in a shortest path tree edge! Difference: " |
---|
| 78 | <<std::abs(dijkstra_test.dist(v) - dijkstra_test.dist(u) |
---|
| 79 | - cap[e])<<std::endl; |
---|
| 80 | ++error2; |
---|
| 81 | } |
---|
| 82 | } |
---|
| 83 | } |
---|
| 84 | |
---|
| 85 | |
---|
| 86 | |
---|
| 87 | std::cout << error1 << " non-tree and " << error2 |
---|
| 88 | << " shortest path tree edge is erroneous."<<std::endl; |
---|
| 89 | |
---|
| 90 | |
---|
| 91 | |
---|
| 92 | std::cout << |
---|
[449] | 93 | "\n\n Testing dijkstra.h with Fibonacci heap implementation fib_heap.h," |
---|
[384] | 94 | <<std::endl; |
---|
| 95 | std::cout<<" on a graph with " << |
---|
| 96 | G.nodeNum() << " nodes and " << G.edgeNum() << " edges..." |
---|
| 97 | << std::endl<<std::endl; |
---|
| 98 | |
---|
| 99 | Dijkstra<Graph, LengthMap, FibHeap> |
---|
| 100 | dijkstra_test2(G, cap); |
---|
| 101 | ts.reset(); |
---|
| 102 | dijkstra_test2.run(s); |
---|
| 103 | std::cout << "elapsed time: " << ts << std::endl; |
---|
| 104 | |
---|
| 105 | error1=0; |
---|
| 106 | error2=0; |
---|
| 107 | |
---|
[449] | 108 | for(G.first(e); G.valid(e); G.next(e)) { |
---|
[384] | 109 | Node u=G.tail(e); |
---|
| 110 | Node v=G.head(e); |
---|
| 111 | if ( dijkstra_test2.dist(v) - dijkstra_test2.dist(u) > cap[e] ) |
---|
| 112 | if ( dijkstra_test2.reached(u) ) { |
---|
| 113 | std::cout<<"Error! dist(head)-dist(tail)- edge_length= " |
---|
| 114 | <<dijkstra_test2.dist(v) - dijkstra_test2.dist(u) |
---|
| 115 | - cap[e]<<std::endl; |
---|
| 116 | ++error1; |
---|
| 117 | } |
---|
| 118 | } |
---|
| 119 | |
---|
[449] | 120 | for(G.first(v); G.valid(v); G.next(v)) { |
---|
[384] | 121 | if ( dijkstra_test2.reached(v) ) { |
---|
| 122 | Edge e=dijkstra_test2.pred(v); |
---|
| 123 | Node u=G.tail(e); |
---|
| 124 | if ( dijkstra_test2.dist(v) - dijkstra_test2.dist(u) != cap[e] ) { |
---|
| 125 | std::cout<<"Error in a shortest path tree edge! Difference: " |
---|
| 126 | <<std::abs(dijkstra_test2.dist(v) - dijkstra_test2.dist(u) |
---|
| 127 | - cap[e])<<std::endl; |
---|
| 128 | ++error2; |
---|
| 129 | } |
---|
| 130 | } |
---|
| 131 | } |
---|
| 132 | |
---|
| 133 | |
---|
| 134 | std::cout << error1 << " non-tree and " << error2 |
---|
| 135 | << " shortest path tree edge is erroneous."<<std::endl; |
---|
| 136 | |
---|
| 137 | |
---|
| 138 | return 0; |
---|
| 139 | } |
---|