fml

#include <iostream>
#include <fstream>

using namespace std;

int t[5001];

int main()
{
    /*
    Varianta 50 III.4)

    int n, x, i;
    ifstream fin("bac.in");
    ofstream fout("bac.out");
    fin >> n;
    for(i = 1; i <= n; i++)
    {
        fin >> x;
        t[x]++;
    }
    for(i = 0; i <= 5000; i++)
        if(t[i] >= 2)
            fout << i << " ";
    fin.close();
    fout.close();


    Varianta 51 II.5)

    char s[52];
    cin.get(s, 52);
    char lit;
    int nr;
    for(int i = 0; s[i] != NULL; i++)
    {
        lit = s[i++];
        nr = s[i] - 48;
        for(int j = 1; j <= nr; j++)
            cout << lit;
    }
    */
    int n, a[101], i, j;
    ifstream fin("date.in");
    fin >> n;
    for(i = 0; i < n; i++)
        fin >> a[i];
    for(i = 0; i < n-1; i++)
        for(j = i+1; j < n; j++)
            if((a[i] % 2) == (a[j] % 2))
                cout << a[i] << " " << a[j] << "\n";
    fin.close();
    return 0;
}