def getLinearSVMStrs(Cs, s=1):
    """Returns linear svm strings.
    Cs is the set of slack variables to try.
    s is the solver to use:
        1 -- L2-regularized L2-loss support vector classification (dual) [default]
        2 -- L2-regularized L2-loss support vector classification (primal)
        3 -- L2-regularized L1-loss support vector classification (dual)
        5 -- L1-regularized L2-loss support vector classification
    """
    assert int(s) in [1,2,3,5]
    ret = []
    for c in Cs:
        svmstr = '-q -s %s' % (s,)
        if c:
            svmstr += ' -c %s' % (c,)
        ret.append(svmstr)
    return ret