Output of the first code:
# A tibble: 3 x 4
Date Day Time `AM/PM`
<chr> <chr> <time> <chr>
1 1/1/18 Mon 09:23 AM
2 1/1/18 Mon 16:02 PM
3 1/1/18 Mon 22:01 PM
And the second:
# A tibble: 3 x 4
Date Day Time `AM/PM`
<date> <chr> <time> <chr>
1 2018-01-01 Mon 09:23 AM
2 2018-01-01 Mon 16:02 PM
3 2018-01-01 Mon 22:01 PM