#include<cstdio>
#include<fstream>
#include<iostream>
#include<iomanip>
#include<algorithm>
#include<vector>
#include<bitset>
#include<deque>
#include<queue>
#include<set>
#include<map>
#include<cmath>
#include<cstring>
#include<ctime>
#include<cstdlib>
#include<unordered_map>

#define ll long long
#define pb push_back
#define mp make_pair
#define pii pair<int,int>
#define pll pair<ll,ll>

using namespace std;

const int nmax = 100005;

int n, k, i, a[nmax];
ll l, r, m, sol;

bool check(ll x)
{
    ll s = 0;

    for(int i = 1; i <= n; i++)
        s += min(1LL * a[i], x);

    return s >= x * k;
}

int main()
{
    freopen("grupuri.in", "r", stdin);
    freopen("grupuri.out", "w", stdout);

    scanf("%d%d", &k, &n);

    for(i = 1; i <= n; i++)
        scanf("%d", &a[i]);

    l = 1;
    r = 100000000000LL;
    while(l <= r)
    {
        m = (l + r) / 2;
        if(check(m))
        {
            sol = m;
            l = m + 1;
        }
        else r = m - 1;
    }

    printf("%lld\n", sol);

    return 0;
}