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Diffstat (limited to 'gcc/ada/a-coprnu.adb')
| -rw-r--r-- | gcc/ada/a-coprnu.adb | 64 |
1 files changed, 64 insertions, 0 deletions
diff --git a/gcc/ada/a-coprnu.adb b/gcc/ada/a-coprnu.adb new file mode 100644 index 00000000000..a27557afd96 --- /dev/null +++ b/gcc/ada/a-coprnu.adb @@ -0,0 +1,64 @@ +------------------------------------------------------------------------------ +-- -- +-- GNAT LIBRARY COMPONENTS -- +-- -- +-- ADA.CONTAINERS.PRIME_NUMBERS -- +-- -- +-- B o d y -- +-- -- +-- Copyright (C) 2004 Free Software Foundation, Inc. -- +-- -- +-- This specification is derived from the Ada Reference Manual for use with -- +-- GNAT. The copyright notice above, and the license provisions that follow -- +-- apply solely to the contents of the part following the private keyword. -- +-- -- +-- GNAT is free software; you can redistribute it and/or modify it under -- +-- terms of the GNU General Public License as published by the Free Soft- -- +-- ware Foundation; either version 2, or (at your option) any later ver- -- +-- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- +-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- +-- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License -- +-- for more details. You should have received a copy of the GNU General -- +-- Public License distributed with GNAT; see file COPYING. If not, write -- +-- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, -- +-- MA 02111-1307, USA. -- +-- -- +-- As a special exception, if other files instantiate generics from this -- +-- unit, or you link this unit with other files to produce an executable, -- +-- this unit does not by itself cause the resulting executable to be -- +-- covered by the GNU General Public License. This exception does not -- +-- however invalidate any other reasons why the executable file might be -- +-- covered by the GNU Public License. -- +-- -- +-- This unit was originally developed by Matthew J Heaney. -- +------------------------------------------------------------------------------ + +package body Ada.Containers.Prime_Numbers is + + -------------- + -- To_Prime -- + -------------- + + function To_Prime (Length : Count_Type) return Hash_Type is + I, J, K : Integer'Base; + Index : Integer'Base; + + begin + I := Primes'Last - Primes'First; + Index := Primes'First; + while I > 0 loop + J := I / 2; + K := Index + J; + + if Primes (K) < Hash_Type (Length) then + Index := K + 1; + I := I - J - 1; + else + I := J; + end if; + end loop; + + return Primes (Index); + end To_Prime; + +end Ada.Containers.Prime_Numbers; |