Question: I'd like to draw vertical/horizontal lines over the entries of a column/row in an array. I find the method to draw horizontal lines at [Draw a horizonal line over the entries of a row in an array](https://tex.stackexchange.com/questions/79741/draw-a-horizonal-line-over-the-entries-of-a-row-in-an-array).
But when I used the same way to draw the vertical lines. It didn't look well.
My codes are:

```
\usepackage{tikz}
\usetikzlibrary{calc}
\newcommand{\tikzmark}[1]{\tikz[overlay,remember picture] \node (#1) {};}
\newcommand{\DrawLine}[3][]{%
\begin{tikzpicture}[overlay,remember picture]
    \draw [#1] ($(#2)+(0,0.6ex)$) -- ($(#3)+(0,0.6ex)$);
\end{tikzpicture}%
}%

\begin{displaymath}
\left[
\begin{array}{cccc}
\tikzmark{11}{15} & 0 & \tikzmark{13}{0} &0\tikzmark{14} \\
0 & 50 & 20 & 25 \\
35 & 5 & 0 & 10\\
\tikzmark{41}{0} & 65 & \tikzmark{43}{50} & 65
\end{array}
\right].
\DrawLine[black,thick]{11}{14}
\DrawLine[black,thick]{11}{41}
\DrawLine[black,thick]{13}{43}
\end{displaymath}

```

The result looks like 

![enter image description here](https://i.stack.imgur.com/ResXR.png)

But the result I want is 

![enter image description here](https://i.stack.imgur.com/YP4cZ.png)

Does anyone know how to fix this?
Thank you.

Answer: 
No real need for TikZ here, although I would not pretend this solution is very robust.

```
\documentclass{article}
\begin{document}
$$\left[\begin{array}{cccc}
\smash{\vrule width .5pt depth 42pt height 4pt}&&
\smash{\vrule width .5pt depth 42pt height 4pt}\\[-8pt]
\hbox to 0pt{\vrule width 1in depth -3pt height 3.5pt\hss}
15&0&0&0\\
0&50&20&25\\
35&5&0&10\\
0&65&50&65
\end{array}\right]$$
\end{document}

```

![enter image description here](https://i.stack.imgur.com/zJEAh.png)
Without `tikzmark` or `matrix of nodes` , a simple solution is to use the `\rule` command with proper adjustment of `lift`, `width`, and `length`. Here is how to implement this:

```
\documentclass{article} 
\usepackage{amsmath}
\begin{document}
\[\begin{bmatrix}
  15\makebox(-10,0){\rule[-18.5ex]{0.4pt}{4\normalbaselineskip}} 
     & 0 & 0 \makebox(-5,0){\rule[-18.5ex]{0.4pt}{4\normalbaselineskip}} 
             \makebox(-25,0){\rule[1.5ex]{6\normalbaselineskip}{0.4pt}} 
               & 0 \\
  0  & 50 & 20 & 25 \\
  35 & 5  & 0  & 10 \\
  0  & 65 & 50 & 65
\end{bmatrix}\]
\end{document}

```

The output as required:

![enter image description here](https://i.stack.imgur.com/XY6Wm.png)