Example Program
Floyd-Warshall Algorithm
Computing all-pairs shortest paths using Floyd-Warshall algorithm.
A tutorial about the Floyd-Warshall algorithm.
1#include <iostream>
2#include <seqan/graph_algorithms.h>
3
4using namespace seqan;
5
6int main() {
7    typedef Graph<Directed<> > TGraph;
8    typedef VertexDescriptor<TGraph>::Type TVertexDescriptor;
9    typedef EdgeDescriptor<TGraph>::Type TEdgeDescriptor;
10    typedef Size<TGraph>::Type TSize;
Graph creation: 9 directed edges (0,1), (0,2), ...
11    TSize numEdges = 9;
12    TVertexDescriptor edges[] = {0,1, 0,2, 0,4, 1,3, 1,4, 2,1, 3,0, 3,2, 4,3};
13    TGraph g;
14    addEdges(g,edges, numEdges);
15    ::std::cout << g << ::std::endl;
One external property map: Weight map
16    int weights[] =    {3,   8,   -4,  1,   7,   4,   2,   -5,  6};
17    String<int> weightMap;
18    resizeEdgeMap(g,weightMap, weights);
Out-parameters: Predecessor and distance matrices
19    String<int> distMat;
20    String<TVertexDescriptor> predMat;
Floyd-Warshall
21    floydWarshallAlgorithm(g,weightMap, distMat, predMat);
Console Output
22    unsigned int len = (unsigned int) std::sqrt((double) length(distMat));
23    for (TSize row=0;row < len;++row) {
24        for (TSize col=0;col < len;++col) {
25            ::std::cout << row << "," << col << " (Distance=" << getValue(distMat, row*len + col) << "): "; 
26            _printAllPairsShortestPath(g,predMat,row,col);
27            ::std::cout << ::std::endl;
28        }
29    }
30    return 0;
31}
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