#include <cstdio>
#include <cstdlib>
#include <cmath>
using namespace std;

int v[100010], N, K;
long long S;

int main()
{
    freopen("grupuri.in", "r", stdin);
    freopen("grupuri.out", "w", stdout);
    int i;
    scanf("%i %i", &K, &N);
    for(i = 1; i <= N; i++) scanf("%i", &v[i]), S += 1LL * v[i];
    i = N;
    while(S / K <= v[i])
    {
            S -= v[i --];
            K --;
    }
    printf("%lld\n", S / K);
    return 0;
}