What are the cheapest cloud computing?

Question

Cloud computing

Advise the cheapest cloud computing
possible that work on the residual principle, i.e. allocate a processor if others don't need it

Answer 1

I don’t know how the price is relative to others, but amazon
pay only for the resources that you use

Answer 2

Spot instances at Amazon, Google has something similar.
But in practice, some flops will come out cheaper if you don't need a lot of resources. And there are even cheaper deals on the market.