git push报错，有时会出现如下情况，网络问题：

$ git push
fatal: unable to access 'https://github.com/yaofanghao/cpp.git/': Failed to connect to github.com port 443 after 21115 ms: Timed out

解决方案：
按顺序输入以下命令，成功

git config --global http.proxy http://127.0.0.1:1080
git config --global https.proxy http://127.0.0.1:1080
git config --global --unset http.proxy
git config --global --unset https.proxy
git push