circle packing request

sorry, if this has been posted before. i have been searching the archives for some hours, but could not get, what i am after.

i need circle packing for two different cases:

task #1: pack circles of 5 different fixed radii into a planar surface (with a hole)

task #2: pack circles of 5 different fixed radii into a curved surface or a mesh

in both cases the space between the circles should be as small as possible. does anybody already have a solutions for these tasks and can share them here? any help would be greatly appreciated.