algorithm LRU, how many bits needed for implement this algorithm?

algorithm, cpu-cache, lru

Solution

There is a good slide-deck at http://www.powershow.com/view/95163-NzkyO/4_4_Page_replacement_algorithms_powerpoint_ppt_presentation that talks about various page replacement schemes. It also explains the LRU implementation using mxm matrix really well.

Problem

I have a little question about the algorithm LRU. If you have a cache with four blocs , how many bits do you need to implement this algorithm ?

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