//GNU Library General Public License (LGPL)
//http://dac.codeplex.com/license
using System;
using System.Runtime.ConstrainedExecution;
namespace RaisingStudio.Collections.Generic
{
internal static class HashHelpers
{
internal static readonly int[] primes = new int[] {
3, 7, 11, 0x11, 0x17, 0x1d, 0x25, 0x2f, 0x3b, 0x47, 0x59, 0x6b, 0x83, 0xa3, 0xc5, 0xef,
0x125, 0x161, 0x1af, 0x209, 0x277, 0x2f9, 0x397, 0x44f, 0x52f, 0x63d, 0x78b, 0x91d, 0xaf1, 0xd2b, 0xfd1, 0x12fd,
0x16cf, 0x1b65, 0x20e3, 0x2777, 0x2f6f, 0x38ff, 0x446f, 0x521f, 0x628d, 0x7655, 0x8e01, 0xaa6b, 0xcc89, 0xf583, 0x126a7, 0x1619b,
0x1a857, 0x1fd3b, 0x26315, 0x2dd67, 0x3701b, 0x42023, 0x4f361, 0x5f0ed, 0x72125, 0x88e31, 0xa443b, 0xc51eb, 0xec8c1, 0x11bdbf, 0x154a3f, 0x198c4f,
0x1ea867, 0x24ca19, 0x2c25c1, 0x34fa1b, 0x3f928f, 0x4c4987, 0x5b8b6f, 0x6dda89
};
internal static int GetMinPrime()
{
return primes[0];
}
[ReliabilityContract(Consistency.WillNotCorruptState, Cer.Success)]
internal static int GetPrime(int min)
{
for (int i = 0; i < primes.Length; i++)
{
int num2 = primes[i];
if (num2 >= min)
{
return num2;
}
}
for (int j = min | 1; j < 0x7fffffff; j += 2)
{
if (IsPrime(j))
{
return j;
}
}
return min;
}
[ReliabilityContract(Consistency.WillNotCorruptState, Cer.Success)]
internal static bool IsPrime(int candidate)
{
if ((candidate & 1) == 0)
{
return (candidate == 2);
}
int num = (int)Math.Sqrt((double)candidate);
for (int i = 3; i <= num; i += 2)
{
if ((candidate % i) == 0)
{
return false;
}
}
return true;
}
}
}
|
