#include <stdio.h>

int a[100100];
int n,k;

int f(int n,int k, int suma)
{
    int i;
    if (suma/k>=a[n])
         return suma/k;
         else
         f(n-1,k-1,suma-a[n]);
}


int main()
{
    int i,suma=0;
    freopen("grupuri.in","r",stdin);
    freopen("grupuri.out","w",stdout);
    
    scanf("%d %d", &k, &n);
    for (i=1;i<=n;++i)
          {
             scanf("%d", &a[i]);
             suma+=a[i];
          }  
    printf("%d", f(n,k,suma));
    return 0;
}