#include <cstdio>
#include <algorithm>
#define LL long long
using namespace std;
const int nmax=100004;
int v[nmax],n,k;
LL sum,ans;
int main()
{
    freopen ("grupuri.in","r",stdin);
    freopen ("grupuri.out","w",stdout);
    scanf("%d%d",&k,&n);
    for(int i=1;i<=n;i++)
    {
        scanf("%d",&v[i]);
        sum+=v[i];
    }
    LL st=0,dr=sum/k;
    while(st<=dr)
    {
        sum=0;
        LL mij=(st+dr)/2;
        for(int i=1;i<=n;i++) sum+=min(1LL*v[i],mij);
        if(sum/k>=mij)
        {
            ans=sum/k;
            st=mij+1;
        }
        else dr=mij-1;
    }
    printf("%lld\n",ans);
}