We present necessary and sufficient conditions when a certain greedy object selection algorithm gives optimal results. Our approach covers known results for the Unbounded Knapsack Problem and Change Making Problem and gives new theoretical results for a variety of packing problems. We also provide connections between packing problems and certain bidirectional capacity installation problems on networks.

中文翻译：

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当贪婪给出最优时：统一方法

当某种贪婪对象选择算法给出最优结果时，我们提出了充要条件。我们的方法涵盖了无界背包问题和找零问题的已知结果，并为各种包装问题提供了新的理论结果。我们还提供打包问题和网络上某些双向容量安装问题之间的联系。