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Simplify negativity checks in math.comb and math.perm. (GH-13870)

This commit is contained in:
Mark Dickinson 2019-06-16 11:06:06 +01:00 committed by GitHub
parent 552951563c
commit 45e0411eee
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GPG Key ID: 4AEE18F83AFDEB23
1 changed files with 16 additions and 10 deletions
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26
Modules/mathmodule.c
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@ -3056,6 +3056,12 @@ math_perm_impl(PyObject *module, PyObject *n, PyObject *k)
"n must be a non-negative integer");
goto error;
}
if (Py_SIZE(k) < 0) {
PyErr_SetString(PyExc_ValueError,
"k must be a non-negative integer");
goto error;
}
cmp = PyObject_RichCompareBool(n, k, Py_LT);
if (cmp != 0) {
if (cmp > 0) {
@ -3072,11 +3078,8 @@ math_perm_impl(PyObject *module, PyObject *n, PyObject *k)
LLONG_MAX);
goto error;
}
else if (overflow < 0 || factors < 0) {
if (!PyErr_Occurred()) {
PyErr_SetString(PyExc_ValueError,
"k must be a non-negative integer");
}
else if (factors == -1) {
/* k is nonnegative, so a return value of -1 can only indicate error */
goto error;
}
@ -3176,6 +3179,12 @@ math_comb_impl(PyObject *module, PyObject *n, PyObject *k)
"n must be a non-negative integer");
goto error;
}
if (Py_SIZE(k) < 0) {
PyErr_SetString(PyExc_ValueError,
"k must be a non-negative integer");
goto error;
}
/* k = min(k, n - k) */
temp = PyNumber_Subtract(n, k);
if (temp == NULL) {
@ -3204,11 +3213,8 @@ math_comb_impl(PyObject *module, PyObject *n, PyObject *k)
LLONG_MAX);
goto error;
}
else if (overflow < 0 || factors < 0) {
if (!PyErr_Occurred()) {
PyErr_SetString(PyExc_ValueError,
"k must be a non-negative integer");
}
if (factors == -1) {
/* k is nonnegative, so a return value of -1 can only indicate error */
goto error;
}