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GOT AC

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Removed after AC

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#include <iostream>
#include <vector>
#include <cmath>

using namespace std;

void primeNumbers(vector <int> &prime, int n)
{
  short array[1000000] = {0};
  
  for(int i = 2; i <= sqrt(n); i++)
  {
    if(array[i] == 0)
    {
     for(int k = i+1; k < n; k++)
     {
       if(k % i == 0)
         array[k] = 1;
     }
    }
  }

  for(int i = 3; i < n; i++)
  {
    if(array[i] == 0)
      prime.push_back(i);
  }
}

void gold(vector <int> &prime, int n)
{
	
	for(int i = prime.size() - 1; i >= prime.size()/2; i--)
	{
		for(int k = 0; k <= prime.size()/2; k++)
		{
		  if(prime[i] + prime[k] == n)
		  {
		   cout << n << " = " <<  prime[k] << " + " << prime[i] << endl;
		   return;   
		  }
		  if(prime[i] + prime[k] > n)
			  break;
		}
	}
	cout << "Goldbach's conjecture is wrong." << endl;
}


int main()
{
  vector <int> prime;
  int n;
  
  while(cin >> n)
  {
    if(n == 0)
      break;

    primeNumbers(prime, n);
    gold(prime,n);
	
  }
 
  return 0;
}

Code: Select all

#include <cstdio>
#include <iostream>
#include <cstring>
using namespace std;

bool prima[1000005];

int main()
{
	memset(prima,true,sizeof(prima));
	prima[0] = false;
	prima[1] = false;
	for (long i = 2; i < 1000000; i++)
		if (prima[i])
		{
			long j = 2*i;
			while (j < 1000000)
			{
				prima[j] = false;
				j+=i;	
			}	
		}
	long n;
	scanf("%ld",&n);
	while (n)
	{
		long i = 2;
		bool ada = false;
		while (!ada && i < n/2)
		{
			if (prima[i] && prima[n-i])
			{
				ada = true;
				printf("%ld = %ld + %ld\n",n,i,n-i);
			}	
			i++;
		}
		if ( !ada) printf("Goldbach's conjecture is wrong.\n");
		scanf("%ld",&n);	
	}
	return 0;
}

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AC