一、题目

二、代码

#include <iostream>
using namespace std;
bool isPrime(int num)//判断素数
{
    if (num <= 1)
        return false;
    if (num == 2)
        return true;
    if (num % 2 == 0)
        return false;
    for (int i = 3; i < num; i++)
    {
        if (num % i == 0)
        {
            return false;
        }
    }

    return true;
}
int main() {
    int x;
    cin >> x;
    int average = x / 2;


    int a = average, b = average;
    if (isPrime(a) && isPrime(b))
    {
        cout << a << endl;
        cout << b;
        return 0;
    }
    while (true)
    {
        --a;
        ++b;
        if (isPrime(a) && isPrime(b))
        {
            break;
        }
    }
    cout << a << endl;
    cout << b;

    return 0;
}