Similarity-First Search: A New Algorithm with Application to Robinsonian Matrix Recognition

  title={Similarity-First Search: A New Algorithm with Application to Robinsonian Matrix Recognition},
  author={Monique Laurent and Matteo Seminaroti},
We present a new efficient combinatorial algorithm for recognizing if a given symmetric matrix is Robinsonian, i.e., if its rows and columns can be simultaneously reordered so that entries are monotone nondecreasing in rows and columns when moving toward the diagonal. As main ingredient we introduce a new algorithm, named Similarity-First-Search (SFS), which extends Lexicographic Breadth-First Search (Lex-BFS) to weighted graphs and which we use in a multisweep algorithm to recognize… 

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