#include <iostream>
#include <string>
#include <algorithm>
#include <cmath>
#include <vector>
#include <map>
#include <set>
#include <queue>
#include <stack>

#define MAXN 5000005
#define MAXS 5005
#define ll long long

using namespace std;

int n, k, a[MAXN];

void solve() {
    cin >> n >> k;
    double already = 0;
    for (int i = 0; i < k; i++) {
        int tmp; cin >> tmp;
        already += tmp;
    }
    cout << ((n - k) * -3 + already) / n << " " << ((n - k) * 3 + already) / n << endl;
}

int main() {

    int _ = 1;
    //cin >> _;
    while(_--) {
        solve();
    }
    return 0;
}