public void TestRecursiveSubtract(int val1, int val2, int expected)
 {
     Assert.Equal(expected, RecursiveMath.RecursiveSubtract(val1, val2));
 }
 public void TestRecursiveSubtract()
 {
     Assert.Equal(-1, RecursiveMath.RecursiveSubtract(2, 3));
     Assert.Equal(-3, RecursiveMath.RecursiveSubtract(0, 3));
     Assert.Equal(5, RecursiveMath.RecursiveSubtract(10, 5));
 }