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Prime.cpp
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Prime.cpp
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#include <SDKDDKVer.h>
#include <cstdint>
#include <stdio.h>
#include <tchar.h>
#include <math.h>
#include <stdlib.h>
#define GET_BIT_VALUE(Array, Index) \
(bool)((Array)[(Index) >> 5] & (1 << ((Index) & 0x1F)))
#define SET_BIT_TRUE(Array, Index) \
((Array)[(Index) >> 5] |= (1 << ((Index) & 0x1F)))
#define SET_BIT_FALSE(Array, Index) \
((Array)[(Index) >> 5] &= ~(1 << ((Index) & 0x1F)))
/*
使用改进后的区间素数筛法获取[0,MaxNum]范围内的素数情况
返回的是用malloc分配的记录素数情况的位图
*/
uint32_t* GetPrimeList(uint32_t MaxNum)
{
// 计算内存块大小
size_t size = ((MaxNum + 1) >> 3) + 1;
// 分配一块内存
uint32_t *BitArray = reinterpret_cast<uint32_t*>(malloc(size));
if (BitArray)
{
// 内存块初始化为令偶数的对应位为1且奇数的对应位为0的魔数,假定该范围奇
// 数都是素数且偶数都是合数。
memset(BitArray, 0xAA, size);
// 设1不是质数,2是质数
SET_BIT_FALSE(BitArray, 1);
SET_BIT_TRUE(BitArray, 2);
// 获取[3, sqrt(MaxNum))范围内的质数,因为[2, n]之间的任意所有合数都能
// 由[2, sqrt(n)]内的任意质数组合得到。
uint32_t MaxRange = static_cast<uint32_t>(sqrt(MaxNum));
for (uint32_t CurNum = 3; CurNum < MaxRange + 1; CurNum += 2)
{
// 如果CurNum不为质数,则跳过
if (!GET_BIT_VALUE(BitArray, CurNum)) continue;
// 如果CurNum为质数,则用其筛掉[CurNum^2 ,MaxNum]范围内可以整除该质
// 数的奇合数。因为在之前初始化内存块时已经筛去了全部的偶合数且n能
// 把n^2以上的合数筛掉,[n,n^2]之间的会被比n小的质数筛掉。
for (uint32_t i = CurNum * CurNum; i < MaxNum; i += CurNum << 1)
{
if (GET_BIT_VALUE(BitArray, i)) SET_BIT_FALSE(BitArray, i);
}
}
}
return BitArray;
}
#include <Windows.h>
ULONGLONG M2GetTickCount()
{
LARGE_INTEGER Frequency = { 0 }, PerformanceCount = { 0 };
if (QueryPerformanceFrequency(&Frequency))
{
if (QueryPerformanceCounter(&PerformanceCount))
{
return (PerformanceCount.QuadPart * 1000 / Frequency.QuadPart);
}
}
return GetTickCount64();
}
template<class Function>
void Test(Function func)
{
uint32_t MaxNum = 0x7FFFFFFF;
uint32_t sum = 0;
Sleep(1000);
ULONGLONG StartTime = M2GetTickCount();
uint32_t* BitMap = func(MaxNum);
ULONGLONG EndTime = M2GetTickCount();
wprintf(L"Time = %llu ms\n", EndTime - StartTime);
if (BitMap)
{
for (uint32_t i = 0; i < MaxNum; ++i)
{
if (GET_BIT_VALUE(BitMap, i))
{
++sum;
}
}
printf("%ld\n", sum);
free(BitMap);
}
}
#include <bitset>
#include <vector>
std::vector<uint32_t> GetPrimeListFast(uint32_t MaxNum)
{
size_t size = ((MaxNum + 1) >> 3) + 1;
std::vector<uint32_t> PrimeList;
std::vector<uint32_t> NotPrimeBitArray(size, 0);
uint32_t* pNotPrimeBitArray = &NotPrimeBitArray[0];
SET_BIT_TRUE(pNotPrimeBitArray, 1);
SET_BIT_FALSE(pNotPrimeBitArray, 2);
PrimeList.push_back(2);
uint32_t PrimeCount = 1;
uint32_t* PrimeListPointer = &PrimeList[0];
for (uint32_t i = 3; i < MaxNum; i += 2)
{
if (!GET_BIT_VALUE(pNotPrimeBitArray, i))
{
if (PrimeCount == PrimeList.size())
{
PrimeList.resize(PrimeCount + (2 << 16));
PrimeListPointer = &PrimeList[0];
}
PrimeListPointer[PrimeCount++] = i;
//PrimeList.push_back(i);
}
for (size_t j = 0; j < PrimeCount && i * PrimeListPointer[j] < MaxNum; ++j)
{
SET_BIT_TRUE(pNotPrimeBitArray, i * PrimeListPointer[j]);
if (i % PrimeListPointer[j] == 0) break;
}
}
PrimeList.resize(PrimeCount);
return PrimeList;
}
#define GetBit(Array, BitIndex) static_cast<bool>((Array)[(BitIndex) >> 5] & (1 << ((BitIndex) & 0x1F)))
#define InvertBit(Array, BitIndex) (Array)[(BitIndex) >> 5] ^= 1 << ((BitIndex) & 0x1F)
/*
使用改进后的线性素数筛法获取[0,MaxNum]范围内的素数情况
返回的是用malloc分配的记录素数情况的位图
*/
uint32_t* GetPrimeList2(uint32_t MaxNum)
{
// 计算内存块大小
size_t size = ((MaxNum + 1) >> 3) + 1;
// 分配一块内存
uint32_t* BitArray = reinterpret_cast<uint32_t*>(malloc(size));
if (BitArray)
{
// 内存块初始化为令偶数的对应位为1且奇数的对应位为0的魔数,假定该范围奇
// 数都是素数且偶数都是合数。
memset(BitArray, 0xAA, size);
// 设1不是质数,2是质数
InvertBit(BitArray, 1);
InvertBit(BitArray, 2);
// 获取[3, sqrt(MaxNum))范围内的质数,因为[2, n]之间的任意所有合数都能
// 由[2, sqrt(n)]内的任意质数组合得到。
for (uint32_t p = 3; p <= MaxNum / p; p += 2)
{
if (!GetBit(BitArray, p)) continue;
for (uint32_t i = p; i <= MaxNum / p; i += 2)
{
if (!GetBit(BitArray, i)) continue;
for (uint64_t j = i * p; j <= MaxNum; j *= p)
{
InvertBit(BitArray, j);
}
}
}
}
return BitArray;
}
int main()
{
uint32_t MaxNum = 0x7FFFFFFF;
uint32_t sum = 0;
Sleep(1000);
ULONGLONG StartTime = M2GetTickCount();
uint32_t* BitMap = GetPrimeList2(MaxNum);
ULONGLONG EndTime = M2GetTickCount();
wprintf(L"Time = %llu ms\n", EndTime - StartTime);
if (BitMap)
{
for (uint32_t i = 0; i < MaxNum; ++i)
{
if (GetBit(BitMap, i))
{
++sum;
}
}
printf("%ld\n", sum);
free(BitMap);
}
return 0;
}
int main1()
{
//Test<>(&GetPrimeList);
Sleep(1000);
ULONGLONG StartTime = M2GetTickCount();
std::vector<uint32_t> PrimeList = GetPrimeListFast(0x7FFFFFFF);
ULONGLONG EndTime = M2GetTickCount();
wprintf(L"Time = %llu ms\n", EndTime - StartTime);
printf("%llu\n", PrimeList.size());
return 0;
}