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// @(#)root/base:$Id$
// Authors: Rene Brun 08/02/2007
/*************************************************************************
* Copyright (C) 1995-2007, Rene Brun and Fons Rademakers. *
* All rights reserved. *
* *
* For the licensing terms see $ROOTSYS/LICENSE. *
* For the list of contributors see $ROOTSYS/README/CREDITS. *
*************************************************************************/
/** TMath Base functions
\ingroup Base
Define the functions Min, Max, Abs, Sign, Range for all types.
NB: These functions are unfortunately not available in a portable
way in std::.
More functions are defined in TMath.h. TMathBase.h is designed to be
a stable file and used in place of TMath.h in the ROOT miniCore.
*/
#include "TMathBase.h"
#include <math.h>
////////////////////////////////////////////////////////////////////////////////
/// Return next prime number after x, unless x is a prime in which case
/// x is returned.
Long_t TMath::NextPrime(Long_t x)
{
if (x <= 2)
return 2;
if (x == 3)
return 3;
if (x % 2 == 0)
x++;
Long_t sqr = (Long_t) sqrt((Double_t)x) + 1;
for (;;) {
Long_t n;
for (n = 3; (n <= sqr) && ((x % n) != 0); n += 2)
;
if (n > sqr)
return x;
x += 2;
}
}
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