g++ answer.cpp -o answer.exe # for submit
g++ answer.cpp -o answer.exe -DLOCAL # for debug
./answer.exe < example1.in
./answer.exe < example2.in
$ brew install gcc
$ ln -s /usr/local/bin/gcc-8 /usr/local/bin/gcc
$ ln -s /usr/local/bin/g++-8 /usr/local/bin/g++
$ open /Library/Developer/CommandLineTools/Packages/macOS_SDK_headers_for_macOS_10.14.pkg