A Two-Level Search Strategy for Packing Unequal Circles into a Circle Container

We propose a two-level search strategy to solve a two dimensional circle packing problem. At the first level, a good enough packing algorithm called A1.0 uses a simple heuristic to select the next circle to be packed. This algorithm is itself used at the second level to select the next circle to be packed. The resulted packing procedure called A1.5 considerably improves the performance of the algorithm in the first level, as shown by experimental results. We also apply the approach to solve other CSPs and obtain interesting results.