Di-chlor is almost always in powdered form, but I have seen 1" tablets once in a blue moon. For every 10ppm of Free Chlorine, Di-chlor adds about 9ppm of CYA.
Tri-chlor most commonly comes in 3" tablets and is VERY acidic and for every 10ppm of FC adds 6ppm of CYA.

Bleach is pH neutral and adds nothing but chlorine.