#include <iostream>
#include <vector>
using namespace std;
 
class SumTwoPrimes
{
	private:
	size_t n;
	vector<size_t> primes,lows;
	public:
	SumTwoPrimes(size_t n):n(n) 
	{
		PrimesOver2();
		SumPrimes();
		primes.resize(0);
	}
	size_t oposite(size_t p)const { return n-p; }
	const vector<size_t> &list()const { return lows; }
	protected:
	void PrimesOver2()
	{
		vector<bool> bin(n+1);
		for(size_t i=3;i<=n;i+=2)
		{
			if(!bin[i])
			{
				primes.push_back(i);
				for(size_t k=i<<1;k<=n;k+=i) bin[k]=true;
			}
		}
	}
	void SumPrimes()
	{
		for(int fr=0,bk=primes.size()-1;fr<=bk;)
		{
			size_t pfr=primes[fr],sum=pfr+primes[bk];
			if(sum>n) --bk;
			else if(sum<n) ++fr;
			else
			{
				lows.push_back(pfr);
				++fr;
				--bk;
			}
		}
	}
};
 
int main() 
{
	SumTwoPrimes stp(1000);
	for(auto p:stp.list()) cout<<p<<" + "<<stp.oposite(p)<<endl;
	return 0;
}

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