#include <cstdio>

using namespace std;

FILE *fin = freopen("grupuri.in", "r",stdin);
FILE *fout = freopen("grupuri.out","w",stdout);

static const int NMAX = 1e5+5;

int n,k;
int v[NMAX];
int sumTotal;
int logN, pas;
int main()
{
    scanf("%d%d",&k,&n);

    for(int i= 1; i<= n; ++i)
    {
        scanf("%d",&v[i]);
        sumTotal+=v[i];
    }
    for(logN = 1; logN <= sumTotal; logN<<=1);

    for(;logN; logN >>=1)
    {
        if((pas+logN)*k <= sumTotal)
            pas+=logN;
    }

    printf("%d", pas);
    return 0;
}