See below program:
m1(int x, int y) if (x<0) and (y>0) print("only x is negative") else if (x>0) and (y<0) print("only y is negative") end m1
I think the equivalence partitioning for y includes y<0, y=0 and y>0. Similarly for x. When x and y are considered together, I think we have 9 equivalence classes (for example, one is when x>0 and y>0 and so on).
However, I have no idea how to write the boundary value analysis and relevant test cases. Most of the reference I found deal with the case when each x and y are ranges of values. Could you please help me?