src/HOL/SPARK/Examples/Sqrt/Sqrt.adb
author wenzelm
Mon, 13 Apr 2020 22:08:14 +0200
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tuned NEWS;
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package body Sqrt is
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   function Isqrt(N: Natural) return Natural
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   is
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     R: Natural;
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   begin
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      R := 0;
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      loop
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         --# assert R * R <= N;
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         exit when N - R * R < 2 * R + 1;
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         R := R + 1;
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      end loop;
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      return R;
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   end Isqrt;
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end Sqrt;