refactor and improve the round trip computation of multiple SCCs

Problem:
- old solution was slow
- depending on the result of TarjanSCC, new distance tables and new phantom node vectors were created to run tsp on it

Solution:
- dont create new distance tables and phantom node vectors
- pass an additional vector with the information which locations are in the same component and ignore all others

fix bug for scc split computation

data_structures/matrix_graph_wrapper.hpp

@@ -0,0 +1,66 @@
+/*
+
+Copyright (c) 2015, Project OSRM contributors
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without modification,
+are permitted provided that the following conditions are met:
+
+Redistributions of source code must retain the above copyright notice, this list
+of conditions and the following disclaimer.
+Redistributions in binary form must reproduce the above copyright notice, this
+list of conditions and the following disclaimer in the documentation and/or
+other materials provided with the distribution.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
+ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+*/
+
+#ifndef MATRIX_GRAPH_WRAPPER_H
+#define MATRIX_GRAPH_WRAPPER_H
+
+#include <vector>
+
+//This Wrapper provides all methods that are needed for TarjanSCC, when the graph is given in a
+//matrix representation (e.g. as output from a distance table call)
+
+template <typename T> class MatrixGraphWrapper {
+public:
+
+    MatrixGraphWrapper(std::vector<T> table, const unsigned number_of_nodes) : table_(table), number_of_nodes_(number_of_nodes) {};
+
+    unsigned GetNumberOfNodes() {
+        return number_of_nodes_;
+    }
+
+    std::vector<unsigned> GetAdjacentEdgeRange(const unsigned node) const {
+        std::vector<unsigned> edges;
+        const auto maxint = std::numeric_limits<int>::max();
+        for (auto i = 0; i < number_of_nodes_; ++i) {
+            if (*(table_.begin() + node * number_of_nodes_ + i) != maxint) {
+                edges.push_back(i);
+            }
+        }
+        return edges;
+    }
+
+    unsigned GetTarget(const unsigned edge) {
+        return edge;
+    }
+
+private:
+    std::vector<T> table_;
+    const unsigned number_of_nodes_;
+};
+
+
+#endif // MATRIX_GRAPH_WRAPPER_H