Valid mask characters are HH (hour), MM (minute), SS (second), *s, and special characters. Seconds are optional.
Append your format with asterisks to indicate the AM and PM indicators that you specify, using a one-to-one correspondence. For example, if your indicators are A.M. and P.M., append **** to your format; if they are AM and PM, append ** to your format.
Hours, minutes, and seconds must be in the same order in both the input and output formats. For example:
| Input Format | HHMMSS |
| Output Format | HH.MM.SS** |