makao / lpsolve Goto Github PK

I know my problem is not for this package but it seems this is the only place to ask so please help me if you can.

I am trying to use the lpsolve package and I am getting the following error.

composer require makao/lpsolve
Using version dev-master for makao/lpsolve
./composer.json has been updated
Loading composer repositories with package information
Updating dependencies (including require-dev)
Your requirements could not be resolved to an installable set of packages.

Problem 1
- Installation request for makao/lpsolve dev-master -> satisfiable by makao/lpsolve[dev-master].
- makao/lpsolve dev-master requires ext-lpsolve >=5.5.0.8 -> the requested PHP extension lpsolve is missing from your system.

To enable extensions, verify that they are enabled in your .ini files:
- C:\xampp\php\php.ini
You can also run php --ini inside terminal to see which files are used by PHP in CLI mode.

Installation failed, reverting ./composer.json to its original content.

So I am missing the lpsolve extension. I have downloaded the dll file, placed it in the xampp php extensions folder and included in the php.ini file. But it's not working at all.
Any help would be much appreciated

In PHP 7.2 there is now the following exception when trying to use the LE, GE, EQ constants:

ErrorException: Use of undefined constant LE - assumed 'LE' (this will throw an Error in a future version of PHP)