Bachgold_Problem_749_A.cpp

#include <bits/stdc++.h>
using namespace std;

int main()
{
    int n;
    cin >> n;
    cout << n / 2 << endl;
    if (n % 2 == 0)
    {
        for (int i = 0; i < n / 2; i++)
        {
            cout << 2 << " ";
        }
    }
    else
    {
        for (int i = 0; i < n / 2 - 1; i++)
        {
            cout << 2 << " ";
        }
        cout << 3;
    }
    return 0;
}