upgrading IMac Snow Leopard to Yosemite without losing Adobe CS5 suite (photoshop, indesign

I want to upgrade my IMac to Yosemite operating system from Snow Leopard. However, I have Adobe CS5 (photoshop, illustrator & indesign) that was loaded via internet through work but do not have the application cd's for Adobe.

How do I keep my Adobe CS5 suite application if I upgrade to IMac Yosemite?