Even if the thing that you really want is an integral that would be difficult to evaluate.

即使需要计算的,是一个很难的积分。

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And if they're a premade salad then it would be even more difficult because you're not constructing it yourself, so it's hard to uses based on these sort of things.

如果那是预制色拉,就更麻烦了,因为那不是你做的,就很难进行统计

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