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Problem 34

From a hash function to a PRNG

Due: February 9
Points: 1

Recall from data structures class that a hash function \(h(x)\) takes some input integer \(0 \le x \lt m\) and produces an output in the range \(0 \le h(x) \lt n\), for some integers m and n (usually m is much larger than n).

A hash function is definitely not random: if you give it the same input, it must always produce the same output. But a good hash function is said to "appear random" in that there is no discernible relationship between the input and the output.

Describe how a hash function \(h(x)\) as defined above could be used to create a PRNG. What would the parameters of the PRNG be? Do you think this would be a good way to generate pseudo-random numbers?