def xhash(coeff, exp):
    sign = 1
    if coeff < 0:
        sign = -1
        coeff = -coeff
    if exp >= 0:
        exp_hash = pow(10, exp, _PyHASH_MODULUS)
    else:
        exp_hash = pow(_PyHASH_10INV, -exp, _PyHASH_MODULUS)
    hash_ = coeff * exp_hash % _PyHASH_MODULUS
    ans = hash_ if sign == 1 else -hash_
    return -2 if ans == -1 else ans