#include<fstream>
using namespace std;
int n, i, k;
long long s , p, u, mid, ii, jj;
int v[100001];
ifstream fin("grupuri.in");
ofstream fout("grupuri.out");
int main(){
    fin>> k >> n;
    for(i = 1; i <= n; i++){
        fin>> v[i];
        s += v[i];
    }
    p = 1;
    u = s / k;
    while(p <= u){
        mid = (p + u) / 2;
        ii = 1;
        jj = 1;
        for(i = 1; i <= n; i++){
            if(v[i] > mid){
                ii += mid;
                if(ii > mid){
                    jj++;
                    ii-= mid;
                }
            }
            else{
                ii += v[i];
                if(ii > mid){
                    jj++;
                    ii-= mid;
                }
            }
            if(jj > k){
                jj = k;
                ii = mid;
                break;
            }
        }
        if(jj == k && ii == mid){
            p = mid + 1;
        }
        else{
            u = mid - 1;
        }
    }
    fout<< u;
    return 0;
}