sudo apt install g++

1. g++ --version

(base) yongqiang@yongqiang:~$ gcc --version gcc (Ubuntu 7.5.0-3ubuntu1~18.04) 7.5.0 Copyright (C) 2017 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. (base) yongqiang@yongqiang:~$ (base) yongqiang@yongqiang:~$ g++ --version Command 'g++' not found, but can be installed with: sudo apt install g++ (base) yongqiang@yongqiang:~$

2. sudo apt install g++

(base) yongqiang@yongqiang:~$ sudo apt install g++ Reading package lists... Done Building dependency tree Reading state information... Done The following additional packages will be installed: g++-7 libstdc++-7-dev Suggested packages: g++-multilib g++-7-multilib gcc-7-doc libstdc++6-7-dbg libstdc++-7-doc The following NEW packages will be installed: g++ g++-7 libstdc++-7-dev 0 upgraded, 3 newly installed, 0 to remove and 58 not upgraded. Need to get 11.2 MB of archives. After this operation, 42.4 MB of additional disk space will be used. Do you want to continue? [Y/n] y Get:1 http://archive.ubuntu.com/ubuntu bionic-updates/main amd64 libstdc++-7-dev amd64 7.5.0-3ubuntu1~18.04 [1471 kB] Get:1 http://archive.ubuntu.com/ubuntu bionic-updates/main amd64 libstdc++-7-dev amd64 7.5.0-3ubuntu1~18.04 [1471 kB] Get:2 http://archive.ubuntu.com/ubuntu bionic-updates/main amd64 g++-7 amd64 7.5.0-3ubuntu1~18.04 [9697 kB] Get:2 http://archive.ubuntu.com/ubuntu bionic-updates/main amd64 g++-7 amd64 7.5.0-3ubuntu1~18.04 [9697 kB] Get:2 http://archive.ubuntu.com/ubuntu bionic-updates/main amd64 g++-7 amd64 7.5.0-3ubuntu1~18.04 [9697 kB] Get:2 http://archive.ubuntu.com/ubuntu bionic-updates/main amd64 g++-7 amd64 7.5.0-3ubuntu1~18.04 [9697 kB] Get:2 http://archive.ubuntu.com/ubuntu bionic-updates/main amd64 g++-7 amd64 7.5.0-3ubuntu1~18.04 [9697 kB] Get:2 http://archive.ubuntu.com/ubuntu bionic-updates/main amd64 g++-7 amd64 7.5.0-3ubuntu1~18.04 [9697 kB] Get:3 http://archive.ubuntu.com/ubuntu bionic-updates/main amd64 g++ amd64 4:7.4.0-1ubuntu2.3 [1568 B] Fetched 2590 kB in 17min 11s (2511 B/s) Selecting previously unselected package libstdc++-7-dev:amd64. (Reading database ... 34213 files and directories currently installed.) Preparing to unpack .../libstdc++-7-dev_7.5.0-3ubuntu1~18.04_amd64.deb ... Unpacking libstdc++-7-dev:amd64 (7.5.0-3ubuntu1~18.04) ... Selecting previously unselected package g++-7. Preparing to unpack .../g++-7_7.5.0-3ubuntu1~18.04_amd64.deb ... Unpacking g++-7 (7.5.0-3ubuntu1~18.04) ... Selecting previously unselected package g++. Preparing to unpack .../g++_4:7.4.0-1ubuntu2.3_amd64.deb ... Unpacking g++ (4:7.4.0-1ubuntu2.3) ... Setting up libstdc++-7-dev:amd64 (7.5.0-3ubuntu1~18.04) ... Setting up g++-7 (7.5.0-3ubuntu1~18.04) ... Setting up g++ (4:7.4.0-1ubuntu2.3) ... update-alternatives: using /usr/bin/g++ to provide /usr/bin/c++ (c++) in auto mode Processing triggers for man-db (2.8.3-2ubuntu0.1) ... (base) yongqiang@yongqiang:~$

3. which g++

(base) yongqiang@yongqiang:~$ which gcc /usr/bin/gcc (base) yongqiang@yongqiang:~$ (base) yongqiang@yongqiang:~$ which g++ /usr/bin/g++ (base) yongqiang@yongqiang:~$