本文主要是介绍【ProjectEuler】ProjectEuler_050(找到100万以内最多连续素数的和,它也同时是个素数),希望对大家解决编程问题提供一定的参考价值,需要的开发者们随着小编来一起学习吧!
#pragma once#include <windows.h>
#include <vector>
#include <set>using namespace std;class MoonMath
{
public:MoonMath(void);~MoonMath(void);//************************************// Method: IsInt// Access: public// Describe: 判断double值在epsilon的范围内是否很接近整数// 如1.00005在epsilon为0.00005以上就很接近整数// Parameter: double doubleValue 要判断的double值// Parameter: double epsilon 判断的精度,0 < epsilon < 0.5// Parameter: INT32 & intValue 如果接近,返回最接近的整数值// Returns: bool 接近返回true,否则返回false//************************************static bool IsInt(double doubleValue, double epsilon, INT32 &intValue);//************************************// Method: Sign// Access: public// Describe: 获取value的符号// Parameter: T value 要获取符号的值// Returns: INT32 正数、0和负数分别返回1、0和-1//************************************template <typename T>static INT32 Sign(T value);const static UINT32 MIN_PRIMER = 2; // 最小的素数//************************************// Method: IsPrimer// Access: public// Describe: 判断一个数是否是素数// Parameter: UINT32 num 要判断的数// Returns: bool 是素数返回true,否则返回false//************************************static bool IsPrimer(UINT32 num);//************************************// Method: IsIntegerSquare// Access: public static// Describe: 判断给定的数开平方后是否为整数// Parameter: UINT32 num// Returns: bool//************************************static bool IsIntegerSquare(UINT32 num);//************************************// Method: GetDiffPrimerFactorNum// Access: public static// Describe: 获取num所有的不同质因数// Parameter: UINT32 num// Returns: set<UINT32>//************************************static set<UINT32> MoonMath::GetDiffPrimerFactorNum(UINT32 num);
};
#include "MoonMath.h"
#include <cmath>MoonMath::MoonMath(void)
{
}MoonMath::~MoonMath(void)
{
}template <typename T>
INT32 MoonMath::Sign(T value)
{if(value > 0){return 1;}else if(value == 0){return 0;}else{return -1;}
}bool MoonMath::IsInt(double doubleValue, double epsilon, INT32 &intValue)
{if(epsilon > 0.5 || epsilon < 0){return false;}if(INT32(doubleValue + epsilon) == INT32(doubleValue - epsilon)){return false;}INT32 value = INT32(doubleValue);intValue = (fabs(doubleValue - value) > 0.5) ? (value + MoonMath::Sign(doubleValue)) : (value) ;return true;
}bool MoonMath::IsPrimer(UINT32 num)
{if(num < MIN_PRIMER){return false;}UINT32 sqrtOfNum = (UINT32)sqrt((double)num); // num的2次方// 从MIN_PRIMER到sqrt(num),如果任何数都不能被num整除,num是素数,否则不是for(UINT32 i = MIN_PRIMER; i <= sqrtOfNum; ++i){if(num % i == 0){return false;}}return true;
}bool MoonMath::IsIntegerSquare(UINT32 num)
{UINT32 qurtNum = (UINT32)sqrt((double)num);return (qurtNum * qurtNum) == num;
}set<UINT32> MoonMath::GetDiffPrimerFactorNum(UINT32 num)
{UINT32 halfNum = num / 2;set<UINT32> factors;for(UINT32 i = 2; i <= halfNum; ++i){if(!MoonMath::IsPrimer(i)){continue;}if(num % i == 0){factors.insert(i);while(num % i == 0){num /= i;}}}return factors;
}
// Consecutive prime sum
// Problem 50
// The prime 41, can be written as the sum of six consecutive primes:
//
// 41 = 2 + 3 + 5 + 7 + 11 + 13
// This is the longest sum of consecutive primes that adds to a prime below one-hundred.
//
// The longest sum of consecutive primes below one-thousand that adds to a prime, contains 21 terms, and is equal to 953.
//
// Which prime, below one-million, can be written as the sum of the most consecutive primes?#include <iostream>
#include <windows.h>
#include <ctime>
#include <assert.h>#include <vector>
#include <MoonMath.h>using namespace std;// 打印时间等相关信息
class DetailPrinter
{
public:void Start();void End();DetailPrinter();private:LARGE_INTEGER timeStart;LARGE_INTEGER timeEnd;LARGE_INTEGER freq;
};DetailPrinter::DetailPrinter()
{QueryPerformanceFrequency(&freq);
}//************************************
// Method: Start
// Access: public
// Describe: 执行每个方法前调用
// Returns: void
//************************************
void DetailPrinter::Start()
{QueryPerformanceCounter(&timeStart);
}//************************************
// Method: End
// Access: public
// Describe: 执行每个方法后调用
// Returns: void
//************************************
void DetailPrinter::End()
{QueryPerformanceCounter(&timeEnd);cout << "Total Milliseconds is " << (double)(timeEnd.QuadPart - timeStart.QuadPart) * 1000 / freq.QuadPart << endl;const char BEEP_CHAR = '\007';cout << endl << "By GodMoon" << endl << __TIMESTAMP__ << BEEP_CHAR << endl;system("pause");
}/*************************解题开始*********************************///************************************
// Method: MakePrimerVector
// Access: public
// Describe: 获取[0,maxNum]的所有素数,存入primers
// Parameter: UINT32 maxNum 要找的最大值
// Parameter: vector<UINT32> & primers 输出素数数组,素数由小到大排列
// Returns: void
//************************************
void MakePrimerVector(UINT32 maxNum, vector<UINT32> &primers)
{for(UINT32 num = MoonMath::MIN_PRIMER; num <= maxNum; ++num){if(MoonMath::IsPrimer(num)){primers.push_back(num);}}
}//************************************
// Method: GetSum
// Access: public
// Describe: 计算迭代器[itBegin,itEnd)的和
// Parameter: const vector<UINT32>::const_iterator & itBegin
// Parameter: const vector<UINT32>::const_iterator & itEnd
// Returns: UINT32
//************************************
UINT64 GetSum(const vector<UINT32>::const_iterator &itBegin,const vector<UINT32>::const_iterator &itEnd)
{UINT64 sum = 0;for(vector<UINT32>::const_iterator it = itBegin; it != itEnd; ++it){sum += *it;}return sum;
}void TestFun1()
{cout << "Test OK!" << endl;
}void F1()
{cout << "void F1()" << endl;// TestFun1();DetailPrinter detailPrinter;detailPrinter.Start();/*********************************算法开始*******************************/const UINT32 MAX_NUM = 1000000;vector<UINT32> primers;MakePrimerVector(MAX_NUM - 1, primers);UINT32 count = primers.size();UINT64 currSum = 0;bool notFound = true;vector<UINT32>::const_iterator itBegin; // 数列的第一个数vector<UINT32>::const_iterator itEnd; // 数列的最后一个数的下一个元素!itBegin = primers.begin();// numCount为数列中的数字个数for(UINT32 numCount = count; numCount > 0 && notFound; --numCount){itEnd = itBegin + numCount;// 获取第一组数列,索引范围[0,numCount-1]currSum = GetSum(itBegin, itEnd);if(currSum < MAX_NUM && MoonMath::IsPrimer(currSum)){break;}UINT32 remainSetCount = count - numCount; // 剩余的数列个数for(UINT32 setIndex = 0; setIndex < remainSetCount; ++setIndex){// 计算下一组数列和,减去前一个数,加上后一个数currSum = currSum - primers[setIndex] + primers[setIndex + numCount];if(currSum < MAX_NUM && MoonMath::IsPrimer(currSum)){itBegin += setIndex + 1;itEnd += setIndex + 1;notFound = false;break;}}}cout << currSum << " is sum of " << *itBegin << " to " << *(itEnd - 1) << endl;cout<<"sum is "<<GetSum(itBegin,itEnd)<<endl;/*********************************算法结束*******************************/detailPrinter.End();
}//主函数
int main()
{F1();return 0;
}/*
void F1()
997651 is sum of 7 to 3931
sum is 997651
Total Milliseconds is 1.60107e+006
*/
这篇关于【ProjectEuler】ProjectEuler_050(找到100万以内最多连续素数的和,它也同时是个素数)的文章就介绍到这儿,希望我们推荐的文章对编程师们有所帮助!