How do I make a State Table in Tabular?

Question

I want a table that looks similar to this one where Present State and Next State aren't aligned so close to each other and have their own respective columns.

The code I have right now:

        \begin{tabular}{@{}c c c | c c c@{}} \toprule
            \multicolumn{6}{c}{Present State Next State} \\ \cmidrule(r){1-6}
            A & B & C & A & B & C\\ \midrule
            0 & 0 & 0 & 0 & 1 & 0\\
            0 & 0 & 1 & 0 & 1 & 0\\
            0 & 1 & 0 & 0 & 1 & 0\\
            0 & 1 & 1 & 0 & 1 & 0\\ 
            1 & 0 & 0 & 0 & 1 & 0\\
            1 & 0 & 1 & 0 & 1 & 0\\
            1 & 1 & 0 & 0 & 1 & 0\\
            1 & 1 & 1 & 0 & 1 & 0\\
            \bottomrule
        \end{tabular}

What I get from doing the above:

I've looked into the tabular documentation, and there's no explanation for having two columns that have three child columns. Oh, I forgot to mention; I'm using the booktabs package.

Answer 1

\documentclass[a4paper,11pt]{article}
\usepackage[a4paper]{geometry}
\usepackage{booktabs}
\usepackage{array}

\begin{document}

\begin{tabular}{*{6}{wc{7mm}}} \toprule
    \multicolumn{3}{c}{Present State} & 
    \multicolumn{3}{c}{Next State} \\ \cmidrule(lr){1-3}\cmidrule(lr){4-6}
    A & B & C & A & B & C\\ \midrule
    0 & 0 & 0 & 0 & 1 & 0\\
    0 & 0 & 1 & 0 & 1 & 0\\
    0 & 1 & 0 & 0 & 1 & 0\\
    0 & 1 & 1 & 0 & 1 & 0\\ 
    1 & 0 & 0 & 0 & 1 & 0\\
    1 & 0 & 1 & 0 & 1 & 0\\
    1 & 1 & 0 & 0 & 1 & 0\\
    1 & 1 & 1 & 0 & 1 & 0\\
    \bottomrule
\end{tabular}

\end{document}