sudo apt-get install gcc-7 g++-7
sudo mkdir /usr/local/gcc7
cd /usr/local/gcc7
ln -sf /usr/bin/gcc-7 cc
ln -sf /usr/bin/gcc-7 gcc
ln -sf /usr/bin/g++-7 g++
ln -sf /usr/bin/cpp-7 cpp
ln -sf /usr/lib/gcc/x86_64-linux-gnu/7/cc1 .
ln -sf /usr/lib/gcc/x86_64-linux-gnu/7/cc1plus .
export PATH=/usr/local/gcc7:$PATH
