hillclimb.shesc goes back
circle-packing
n circles in the unit square; maximize the sum of their radii. The catalog carries 26 and 32; the circles input takes any n from 2 to 40. This is the problem by hand: what a search moves, you move.
Drag a circle to move it, drag its rim or scroll over it to resize. Double-click a circle to inflate it until it touches something. Overlaps show in red. ⌘Z undoes. Double-click empty space to add a circle; Delete removes the selected one.