n mod m indicates the remainder of the euclidian
division of n by m, ie 0 = (n mod m) = m-1 and
there exists k such that n = (k*m) (n mod m);
n smod m indicates the offset remainder of the
euclidian division of n by m, ie
1 = (n smod m) = m and there exists k such that
n = (k*m) (n smod m);
我知道第一个mod是模，第二个smod是什么呢？