Аннотация:
We consider the problem of recovering a hidden element $s$ of a finite field $\mathbb{F}_q$ of $q$ elements from queries to an oracle that for a given $x \in \mathbb{F}_q$ returns $(x+s)^e$ for a given divisor $e \mid q-1$. We use some techniques from additive combinatorics and analytic number theory that lead to more efficient algorithms than the naive interpolation algorithm; for example, they use substantially fewer queries to the oracle.