** 1、卸载cocoapods ：
sudo gem uninstall cocoapods -v 0.35.0
或者
sudo gem uninstall cocoapods
** 2、继续卸载 ：
sudo gem uninstall cocoapods-core -v 1.0.0
或者
sudo gem uninstall cocoapods-core
**3、清除cocoapods缓存 ：
sudo rm -fr ~/.cocoapods/repos/master
**4、重装cocoapods ：
sudo gem install -n /usr/local/bin cocoapods --pre
