-echo -e "\nInstalling required packages: git, wget, curl, tar"
-echo -e " Required root privileges"
-sudo apt install -y git wget curl tar
+echo -e "\nChecking required packages: wget, curl, tar"
+dpkg -l wget curl tar &>/dev/null || ! echo -e " One or several packages are not installed.\nInstalling required packages\n Root privileges are required" || sudo apt install -y wget curl tar