Consider the following function that calculates x % y for positive integers x and y (that is, x mod y, or the remainder when you take x and divide by y. 10 % 3 = 1). int mod (int x, int y) { int r = x; int k = 0; while (r = y) { r=r-y; k++; } return r; Find an appropriate loop invariant for the while loop of this function,. You do not need to prove the correctness of the loop invariant.