Use the ones with .cus extension. They are binary files in the following
format:

numcols, numrows, nnonzeros
colptrs(1:numcols+1)
rowind(1:nnonzeros)
val(1:nnonzeros)

Everythings is 4 byte integers, except for val of course, which is in
single precision.

They are likely 1-indexed



*_CSR.dat are binary files with following format:
numrows,numcols,nnz
rowptr(0:numrows)
colind(0: nnz-1)
val(0:nnz-1)

in CSR format we saved val in double precision (8 bytes).