App Inventor 2 减去列表全部内容的值

App Inventor 2 minusing value by the whole contents of a list

我想知道在App Inventor中是否有办法将整个列表的内容减去一个值。

例如,如果 list1 = [4, 5, 4, 5] 并且我想做 7 - 4 - 5 - 4 - 5 的减法运算,我如何在 App Inventor 2 中执行此操作?

写一个procedure总结列表然后这样计算7 - sumOfList

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