#include <bits/stdc++.h>
using namespace std;
long long s,i,n,k,v[100010],mid,in,sf,nr;
int main()
{
    ifstream f ("grupuri.in");
    ofstream g ("grupuri.out");
    f>>k>>n;
    for(i=1; i<=n; ++i)
    {
        f>>v[i];
        s+=v[i];
    }
    in=0;
    sf=s/k;
    while(in<=sf)
    {
        mid=(in+sf)/2;
        nr=mid*k;
        for(i=1; i<=n; ++i)
            if(v[i]<=mid)nr-=v[i];
            else nr-=mid;
        if(nr<=0)in=mid+1;
        else sf=mid-1;
    }
    g<<(in+sf)/2;
    return 0;
}