def extract_superkmers(reads_matrix, minimizer_matrix):
    superkmers = [] # Composed of tuples (superkmer, minimizer)
    for read_number, row in minimizer_matrix:
        for v in row:
            minimizer = v & 0b11111111111100000000000000000000
            start = v & 0b00000000000000000000001111111111
            end = v & 0b00000000000011111111110000000000
            superkmers.append((reads_matrix[read_number][start:end], minimizer)
    return superkmers