public void CheckIfExistTest() { var s = new Solution(); int[] arr; arr = new int[] { 10, 2, 5, 3 }; Assert.True(s.CheckIfExist(arr)); arr = new int[] { 7, 1, 14, 11 }; Assert.True(s.CheckIfExist(arr)); arr = new int[] { 3, 1, 7, 11 }; Assert.False(s.CheckIfExist(arr)); }