Modify frame title afterwards

Question

I want my frame title to look something like this:

Exercise 1 a)

I know I could achieve this by doing the following:

\begin{frame}{Exercise 1\hfill a)}

\end{frame}

But I do not want to write \hfill all the time. Also, I can't use the subtitle for the a) as I want to use the subtitle for other stuff.

I thought something like this must be possible:

\begin{frame}{Exercise 1}
   \exnum{a)}
\end{frame}

\newcommand\exnum[1]{\frametitle{\insertframetitle\hfill{#1}}}

But I cannot use \insertframetitle there, and I don't know why.

Does anybody have an idea how to achieve what I want?

Answer 1

Similar approach as @Werner's comment, but instead of hardcoding anything, you could create a macro with two arguments:

\documentclass{beamer}

\newcommand{\mytitle}[2]{\frametitle{#1\hfill#2}}

\begin{document}
    
\begin{frame}
    \mytitle{Exercise}{a)}
\end{frame} 
    
\end{document}