32: Improve solution for Rust track exercise "Nth Prime".

Created by  Aaw9nJhsNmfzFih9mKyNw9mV8CgERXJkRa1kK1Kx3LQH  on September 2, 2021
VH5OFL554R47JLRPRPJK4BPVNEREVXQ7E6F42KN7ADEELB7VGYOAC
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