Can someone help with this

\begin{tabular}{|l|l|l|l|l|l|l|l} & A & B & C & D & E & F & G \\ \hline 1 & a & b & f(a) & f(b) & m & f(m) & \\ \hline 2 & 0 & 2 & 4 & 8 & & \\ \hline 3 & & & & & & & \\ \hline \end{tabular}