#include<stdio.h>
#include<math.h>

long long n, k, a[100701];

long long solve(long long n,long long sum,long long k)
{
  if (n<0 || k<=0) return 0;
  if (a[n]<=sum/(long)k) return sum/(long)k;
  return solve(n-1,sum-a[n],k-1);
}

int main()
{
  long long i, sum=0;
  freopen("grupuri.in","r",stdin);
  freopen("grupuri.out","w",stdout);
  scanf ("%lld%lld",&k,&n);
  for (i=0; i<n; i++)
    {
      scanf("%lld",&a[i]); sum+=(long)a[i];
    }
  printf("%lld\n",solve(n-1,sum,k));
  return 0;
}