@Test
public void test1() {
PowerOf3 p3 = new PowerOf3();
boolean isPowerOf3 = p3.check(1);
assertThat(isPowerOf3, is(true));
}
@Test
public void test19() {
PowerOf3 p3 = new PowerOf3();
boolean isPowerOf3 = p3.check(19);
assertThat(isPowerOf3, is(false));
}