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。

youdao

In the second term, the problem is centralisation of power into the hands of the prime minister and an increasingly small number of advisers who make decisions in private without proper discussion.

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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.

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