Generally, this problem is reduced to quadratic residue problem of modulo a big prime number. But this reduction is not applicable to Optimal Extension Fields (OEF).

一般而言，该问题归结为模大素数的二次剩余问题，但这种归结不能用于最优扩域OEF。

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The problem facing the prime minister was that these latter measures had dealt with largely uncontroversial topics, and a number of far more contentious issues were waiting in the wings.

ECONOMIST: The woeful state of Belgian politics