#include<stdio.h>

FILE *fin,*fout;

long long int a[100001],k,n,s;

int main()
{
    fin=fopen("grupuri.in","r");
    fout=fopen("grupuri.out","w");

    fscanf(fin,"%lld %lld",&k,&n);
    for(int i=1;i<=n;i++)
    {
        fscanf(fin,"%lld",&a[i]);
        s+=a[i];
    }
    while(s/k<a[n])
    {
        s-=a[n];
        k--;
        n--;
    }
    fprintf(fout,"%lld",s/k);
}