Typing a commutative diagram using tikzcd [duplicate]

Question

How do I type this commutative diagram in tikz-cd in overleaf?

I have tried this

\documentclass{amsart}
\usepackage{latexsym,amsmath}
\usepackage{mathtools}
\usepackage{scalerel,stackengine}
\usepackage{tikz-cd}
\begin{document}

\maketitle
\[
\begin{tikzcd}
G \arrow[r,""]\arrow[d,swap,"\Delta"]\arrow[rd,swap,"\id_G"] & 1 \times G \arrow[r,"e \times id_G"]  &
  G \times G \arrow[d,"m"] \\
G \times 1 \arrow[d,"id_G \times e"] \\
G \times G \arrow[r,"m"] & G
\end{tikzcd}
\]
\end{document}

which is not working.

Answer 1

The trick is to consider this as a 3-by-3 matrix. So the diagonal arrow should be rrdd, because it has to jump over two columns and two rows.

Similarly, in the last row you need &&, because the center column has no entry.

\documentclass{article}
\usepackage{amsmath,tikz-cd}

\newcommand{\id}{\mathrm{id}}
\newcommand{\one}{\mathbf{1}}

\begin{document}

\[
\begin{tikzcd}[column sep=3em]
%% first row
G \arrow[r] \arrow[d,swap,"\Delta"] \arrow[rrdd,"\id_G"] &
\one \times G \arrow[r,"e \times \id_G"]  &
G \times G \arrow[dd,"m"] \\
%% second row
G \times \one \arrow[d,swap,"\id_G \times e"] \\
%% third row
G \times G \arrow[rr,"m"] && G
\end{tikzcd}
\]

\end{document}

I increased a tad the column separation, so as to avoid the label in the top row overfilling the arrow.

I'm not sure I'd label that arrow by “Delta” that suggests “diagonal”, but you've the final word on this.