Join and meet
Matrices where all entries are 0s and/or 1s are called zero-one matrices.
Let A = [aij] and B = [bij] be m ? n zero-one matrices.
The join of A and B, denoted by A?B, is the matrix with (i,j)th
The meet of A and B, denoted by A?B, is the matrix with (i,j)th