@Test
 public void testMissingChar0() {
   assertTrue(Hw3pr4.missingChar("kitten", 1).equals("ktten"));
 }
 @Test
 public void testMissingChar9() {
   assertTrue(Hw3pr4.missingChar("chocolate", 8).equals("chocolat"));
 }
 @Test
 public void testMissingChar4() {
   assertTrue(Hw3pr4.missingChar("Hi", 1).equals("H"));
 }
 @Test
 public void testMissingChar8() {
   assertTrue(Hw3pr4.missingChar("code", 3).equals("cod"));
 }
 @Test
 public void testMissingChar3() {
   assertTrue(Hw3pr4.missingChar("Hi", 0).equals("i"));
 }