ubuntu server 18.04 php version code example
Example 1: install php 7.1 on ubuntu 18.04
sudo apt install php7.1 php7.1-common php7.1-opcache php7.1-mcrypt php7.1-cli php7.1-gd php7.1-curl php7.1-mysql
Example 2: install php 7.1 on ubuntu 18.04
sudo apt install software-properties-commonsudo add-apt-repository ppa:ondrej/php