使用git切换仓库地址

1 查看远程仓库地址：git remote show origin
2 切换远程仓库地址：git remote set-url origin xxx(新的仓库地址)
如果是个新的空仓库，执行到此就可以执行git push了

3 获取最新代码：git pull

如果不能获取代码并且提示：

There is no tracking information for the current branch.
Please specify which branch you want to merge with.
See git-pull(1) for details.

git pull <remote> <branch>

If you wish to set tracking information for this branch you can do so with:

git branch --set-upstream-to=origin/<branch> master

则执行下面命令：
git branch --set-upstream-to=origin/当前分支名 远程分支名
如果还提示：$ git pull fatal: refusing to merge unrelated histories,则执行下面命令：git pull origin master allow-unrelated-histories
然后再次更新代码：git pull
如果提示代码冲突：master | MERGING,则执行回退命令：git reset --merge将代码恢复到更新代码之前
如果想回退某个历史版本，执行：git checkout 版本号