Need help with to get numbers from procedure.

[GandraZz]

#include <iostream>
#include <iomanip>
#include <vector>
using namespace std;

int main ()
{
    vector<int>  m;
    
    while (true)
    {
        int a;
        cout << "Enter number: ";
        cin >>a;
        if (a == 0)
            break;
        m.push_back(a);
        
    }

    cout << "Number of elements: " << m.size() << endl;
    
    
    int x=0;
    for (int i=0;i<m.size();i++)
    x+=m[i];
    
    int r = x / m.size();
    int p ;

    p = a < r;
    
    cout << "sum:" << x << endl;
    cout << "average" << r << endl;
    cout << setw(3)<< "2'nd array:" << p << endl;

system("pause");
}

I need help with my homework. i done almost everything and now i need just program to post second array with numbers from first array, that are smaller than average of first array. And I don't know how make numbers from vector(a) to work rest part of my program.
And sorry for my English.