1. A calculation processing apparatus, which executes calculation processing based on a network composed by hierarchically connecting a plurality of processing nodes, said apparatus comprising: memory control means for assigning a partial area of a memory to each of the plurality of processing nodes, storing a calculation result of each processing node in a storable area of the partial area assigned to that processing node, and setting, as storable areas, areas that store the calculation results whose reference by all processing nodes connected to a subsequent stage of that processing node is complete; designation means for designating a processing node, which is to execute calculation processing, of the plurality of processing nodes; determination means for determining, based on storage states of calculation results in partial areas of the memory assigned to the processing node designated by said designation means and to processing nodes connected to a previous stage of the designated processing node, whether or not to execute a calculation of the designated processing node; and execution means for, when said determination means determines that the calculation is executed, controlling to execute calculation processing corresponding to the designated processing node.