#include <bits/stdc++.h>
using namespace std;
#define IO ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0)
typedef long long ll;
const long long N = 3e5 + 7, Mod = 1e9 + 7, INF = 2e18;
ll inv(ll a, ll b = Mod) { return 1 < a ? b - inv(b % a, a) * b / a : 1; }
const int dx[9] = {0, 0, 1, -1, 1, 1, -1, -1, 0};
const int dy[9] = {1, -1, 0, 0, -1, 1, 1, -1, 0};
void solve()
{
    int n, k;
    cin >> n >> k;
    ll sm = 0;
    for (int i = 1; i <= k; i++)
    {
        int x;
        cin >> x;
        sm += x;
    }
    cout << fixed << setprecision(10) << (sm - 3 * (n - k)) * 1.0 / n << " " << (sm + 3 * (n - k)) * 1.0 / n << '\n';
}
int main()
{
    IO;
    int TC = 1;
    // cin >> TC;
    while (TC--)
        solve();
}