Module csr 

Compressed Sparse Row (CSR) matrix format.

CSR is an efficient format for sparse matrices/graphs that enables:

• O(1) access to row start/end positions
• O(degree) iteration over neighbors
• Cache-friendly sequential access patterns

Memory layout:

• row_ptr[i] = starting index in col_idx for row i
• col_idx[row_ptr[i]..row_ptr[i+1]] = column indices (neighbors) of row i
• values (optional) = edge weights

Structs

CsrMatrix

Compressed Sparse Row matrix for graph adjacency.

CsrMatrixBuilder

Builder for CSR matrices.