gplanarity software package provides simple puzzle game involving untangling planar graphs, you can install in your Debian 9 (Stretch) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install gplanarity
gplanarity is installed in your system.
Make ensure the gplanarity package were installed using the commands given below,
$ sudo dpkg-query -l | grep gplanarity *
You will get with gplanarity package name, version, architecture and description in a table
| Distro | Debian 9 stretch |
| Section | Games |
| Package | gplanarity |
| Version | 17906-6 |
| Description | simple puzzle game involving untangling planar graphs |
| Sub Section | Games |