Latin-American Conference on Combinatorics, 
Graphs and Applications 
 
         
    Michele Conforti (Padova University, Italy)    
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    Bicolorings and K-colorings of matrices    
         
   

A K-coloring of a matrix is a partition of its column set into K subsets so that each row satisfies a specified property.
This property is often equivalent to the integrality of a polytope.
We survey the major results in the area, starting from the classical bicoloring theorems of Ghouila-Houri and Berge on bicoloring of Totally Unimodular and balanced matrices and then covering more recent results obtained by Conforti, Cornuejols and Zambelli on colorings of balanced 0,±1 matrices and k-balanced matrices. We will link these results to the integrality of some (generalized) packing and covering polytopes.

   
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