tuto does'tn seem work on memcache

I installed php7.2.8 and I follow this tuto :
https://www.howtoforge.com/tutorial/how-to-install-php-7-on-debian/#-enable-memcache-optional-2
But on memcache after this function :
Prepare he sources by running the phpize command from PHP 7.2.

Code:

/opt/php-7.2/bin/phpize

I have this message appear on server (Debian 9) and it's impssible to continue;

Code:

configuring for:
PHP Api Version:         20170718
Zend Module Api No:      20170718
Zend Extension Api No:   320170718
Cannot find autoconf. Please check your autoconf installation and the
$PHP_AUTOCONF environment variable. Then, rerun this script.

root@ns304677:/usr/local/src/php7.2-build/php-memcache/php-memcached-php7# ./configure --with-php-config=/opt/php-7.2/bin/php-config
-bash: ./configure: Aucun fichier ou dossier de ce type

How to solve that ?

 

Code:

apt-get install autoconf

 

Tk need also to make that before to continue also :

Code:

apt-get install pkg-config