decrease size of table in latex code example

Example 1: change table size latex

\usepackage{graphics}
% ...

\begin{table}
\centering
\resizebox{\columnwidth}{!}{%
\begin{tabular}{r|lll}
\multicolumn{1}{r}{}
& \multicolumn{1}{l}{Heading 1}
& \multicolumn{1}{l}{Heading 2}
& \multicolumn{1}{l}{Heading 3} \\ \cline{2-4}
Row 1 & Cell 1,1 & Cell 1,2 & Cell 1,3 \\
Row 2 & Cell 2,1 & Cell 2,2 & Cell 2,3
\end{tabular}%
}
\end{table}

Example 2: reduce size table latex

\resizebox{3cm}{!}{
  \begin{something}
    something
  \end{something}
  }