Many documents use a specific format for a person's name. Write a program that reads a person's name in the following format:

firstName middleName lastName (in one line)

and outputs the person's name in the following format:

lastName, firstInitial.middleInitial.

Ex: If the input is:

Pat Silly Doe
the output is:

Doe, P.S.
If the input has the following format:

firstName lastName (in one line)

the output is:

lastName, firstInitial.

Ex: If the input is:

Julia Clark
the output is:

Clark, J.