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Prime number additon to get specific value

HumbleAAT (28)
x has to be greater than 2 and even. 

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#include <iostream>
#include <cstdlib>
using namespace std;
int main()
{

	int p1 = 1, p2 = 1, t1 = 0, t2 = 0, x, c1 = 0, c2 = 0;
	bool satisfy = false;
	
	cout << "Enter x: "; cin >> x;
	do
	{
		if(t2 == 0)
		{
			for(int i = x; i >= 2; i--)
			{
				for(int j = 1; j <= i; j++)
				{
					if(i%j == 0)
					{
						if(i/j == i || i/j == 1)
							c1++;
						else
							break;
					}
				}
				if(c1 == 2)
				{
					if(i == (x-1))
					{
						c1 = 0;
					}
					else
					{
						p1 = i;
						cout << "P1 is " << p1 << endl;
						break;
					}
				}
				else
					c1 = 0;
			}
		}
		for(int i = 2; i <= x; i++)
		{
			for(int j = 1; j <= i; j++)
			{
				if(i%j == 0)
				{
					if(i/j == i || i/j == 1)
						c2++;
					else
						break;
				}
			}
			if(c2 == 2)
			{
				if(p2 == t2)
				{
					c2 = 0;
					t2 = 0;
				}
				else
				{
					p2 = i;
					cout << "*New* P2 is " << p2 << endl;
					t2 = p2;
					break;
				}
			}
			else
				c2 = 0;
		}
		if((p1+p2) == x)
		{
			cout << "P1 and P2 are both prime and sum up to x.\n";
			satisfy = true;
		}
	}
	while(satisfy == false);
}


When the second loop gets to five it becomes an infinite output at 5, when the output should simply be the next prime number which is 7. Please help, I'm getting really irritated, been looking for a while. The x is 38. P1 is 31 and should be added with 7 to get 38.
Last edited on
keskiverto (10395)
How about:
FOR EACH prime y that is <= x/2
  z = x - y
  IF z is prime THEN break
Last edited on
HumbleAAT (28)
My i variable in the for loop doesnt increment past 5 for some reason ..... the one for the second for loop.
Last edited on
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