# How does a prefix sum with 8 elements can be computed with three processors?

I would like to know if someone can give me an example of how a prefix sum which contains 8 elements can be computed with just three processors.

Prefix sum

• I have a hard time understanding your question, since a lot of context is missing. Can you explain what is a prefix sum, for example? Also it seems that $n$ is constant, so I'm not sure what you mean by $O(n)$. – Yuval Filmus May 27 '20 at 12:06
• I mean what would be the timing of this algorithm with just three processors. I've inserted a link for a description of what prefix sums are. – ChickenMan May 27 '20 at 12:11
• You can compute the prefix sums using a single processor. The two other processors can stay idle. – Yuval Filmus May 27 '20 at 19:23