#include<stdio.h>
using namespace std;

int v[100017];
int K, n;
int rez, i;
long long S, st, dr, mijl;

int calcul (int x)
{
    int aux = x;
    int nr = 0, i = 1;
    while (nr < K && i <= n)
    {
        if(v[i] > x)
        {
            nr ++;
            i ++;
            continue;
        }
        aux -= v[i];
        if (aux < 1)
        {
            aux += x;
            nr ++;
        }
        i ++;
    }

    if (nr < K)
        return 0;

    return 1;
}

int main ()
{
    FILE *f = fopen ("grupuri.in","r");
    FILE *g = fopen ("grupuri.out","w");
    fscanf (f,"%d %d", &K, &n);

    for(i=1; i<=n; ++i)
    {
        fscanf (f,"%d", &v[i]);
        S += v[i];
    }
    st = 1;
    dr = S / K;
    while (st <= dr)
    {
        mijl = (st + dr) / 2;
        rez = calcul (mijl);
        if (!rez)
            dr = mijl - 1;
        else
            st = mijl + 1;
    }

    fprintf(g, "%lld\n", dr);

    fclose(g);
    fclose(f);
    return 0;
}