Algorithms for multiplying several types of sparse n x n-matrices on dynamically
reconfigurable n x n-arrays are presented. For some classes of sparse matrices constant
time algorithms are given, e.g., when the first matrix has at most kn elements in each
column or in each row and the second matrix has at most kn nonzero elements in each
row, where k is a constant. Moreover, O(kn
) algorithms are obtained for the case that
one matrix is a general sparse matrix with at most kn nonzero elements and the other
matrix has at most k nonzero elements in every row or in every column. Also a lower
bound of Ω(Kn
) is proved for this and other cases which shows that the algorithms are
close to the optimum.