def gf_degree(f):
    """
    Return the leading degree of ``f``.

    Examples
    ========

    >>> from sympy.polys.galoistools import gf_degree

    >>> gf_degree([1, 1, 2, 0])
    3
    >>> gf_degree([])
    -1

    """
    return 1 - len(f)
dataset/ETHPy150Open sympy/sympy/sympy/polys/galoistools.py/gf_degree/swapped operands of `-`