#include <bits/stdc++.h>
#define MAXN 1000
#define MAXV 50010

using namespace std;

ifstream fin("economie.in");
ofstream fout("economie.out");

void read(int& n, int arr[], int& maxi) {
    maxi = INT_MIN;
    fin >> n;
    for (int i = 0; i < n; i++) {
        fin >> arr[i];
        maxi = max(maxi, arr[i]);
    }
}

bool verify(int n, const int arr[], bitset<MAXV>& dp) {
    for (int i = 0; i < n; i++)
        if (dp[arr[i]] == 0)
            return false;
    return true;
}

int main() {
    int n, arr[MAXN], maxi, i;
    bitset<MAXV> dp;
    read(n, arr, maxi);

    for (i = 0; i < n && !verify(n, arr, dp); i++) {
        for (int j = 1; j <= maxi; j++)
            if (j % arr[i] == 0 || (j - arr[i] > 0 && dp[j - arr[i]] == 1))
                dp[j] = true;
    }

    fout << i << '\n';
    for (--i; i >= 0; i--)
        fout << arr[i] << '\n';
    return 0;
}