- The traditional algorithm of Stockmeyer for area minimization of slicing floorplans has time (and space) complexity O(n2) in the worst case, or O(n log n) for balanced slicing. For more than a decade, it is considered the best possible. In this paper, we present a new algorithm of worst-case time (and space) complexity O(n log n), where n is the total number of realizations for the basic blocks, regardless whether the slicing is balanced or not. We also prove (n log n) is the lower bound on the time complexity of any area minimization algorithm. Therefore, the new algorithm not only finds the optimal realization, but also has an optimal running time.