Will my contacts get deleted when I sync my iPhone?

I have an iPhone 4S running iOS 6.0.1. I always sync my iPhone to my computer through iTunes on a mac. I recently purchased a new Mac notebook and I want to sync my iPhone through this computer now instead of the other one. My new notebook is already authorized through the same Apple I. D.
I'm fine and well aware of the applications, music, etc. Products I've purchased through iTunes will be replaced. But will my contacts be replaced?

No the contacts won't be erased unless you erase them yourself.

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