An entry is made in the memo whenever an item, memo and an available size pair is considered.

每当选择一件物品和考虑，一种可行的方案时，都会访问。

麻省理工公开课 - 计算机科学及编程导论课程节选

As soon as the available size goes to 0, I know I can't enter any more items into the memo, right?

一旦可装大小为0时我就知道,我不能再在memo中添加物品了？

麻省理工公开课 - 计算机科学及编程导论课程节选