94 lines
1.8 KiB
C++
94 lines
1.8 KiB
C++
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#include "bfs.h"
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#include "list_to_matrix.h"
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#include <vector>
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#include <queue>
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template <
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typename AType,
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typename DerivedD,
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typename DerivedP>
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IGL_INLINE void igl::bfs(
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const AType & A,
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const size_t s,
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Eigen::PlainObjectBase<DerivedD> & D,
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Eigen::PlainObjectBase<DerivedP> & P)
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{
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std::vector<typename DerivedD::Scalar> vD;
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std::vector<typename DerivedP::Scalar> vP;
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bfs(A,s,vD,vP);
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list_to_matrix(vD,D);
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list_to_matrix(vP,P);
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}
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template <
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typename AType,
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typename DType,
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typename PType>
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IGL_INLINE void igl::bfs(
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const std::vector<std::vector<AType> > & A,
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const size_t s,
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std::vector<DType> & D,
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std::vector<PType> & P)
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{
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// number of nodes
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int N = s+1;
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for(const auto & Ai : A) for(const auto & a : Ai) N = std::max(N,a+1);
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std::vector<bool> seen(N,false);
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P.resize(N,-1);
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std::queue<std::pair<int,int> > Q;
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Q.push({s,-1});
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while(!Q.empty())
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{
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const int f = Q.front().first;
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const int p = Q.front().second;
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Q.pop();
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if(seen[f])
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{
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continue;
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}
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D.push_back(f);
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P[f] = p;
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seen[f] = true;
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for(const auto & n : A[f]) Q.push({n,f});
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}
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}
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template <
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typename AType,
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typename DType,
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typename PType>
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IGL_INLINE void igl::bfs(
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const Eigen::SparseMatrix<AType> & A,
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const size_t s,
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std::vector<DType> & D,
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std::vector<PType> & P)
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{
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// number of nodes
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int N = A.rows();
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assert(A.rows() == A.cols());
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std::vector<bool> seen(N,false);
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P.resize(N,-1);
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std::queue<std::pair<int,int> > Q;
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Q.push({s,-1});
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while(!Q.empty())
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{
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const int f = Q.front().first;
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const int p = Q.front().second;
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Q.pop();
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if(seen[f])
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{
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continue;
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}
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D.push_back(f);
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P[f] = p;
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seen[f] = true;
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for(typename Eigen::SparseMatrix<AType>::InnerIterator it (A,f); it; ++it)
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{
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if(it.value()) Q.push({it.index(),f});
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}
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}
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}
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