Which folder should I remove to upgrade my installation using Composer?

Hello,

i am facing one problem, i installed magento 2 using https://github.com/magento/magento2

now i want to update using composer , is there any way which folder i need to remove it?

Composer uses the magento/magento2 GitHub repository too, so your question is incorrect.
You can learn it from the root github.com/magento/magento2/blob/2.1.7/composer.json file.

but i that git repo app/code/Magento contain all code and in composer setup vendor/magento

So i want to know which folder i need to remove.

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