#include <stdio.h>

using namespace std;

long long v[100001];

int main()
{
    freopen("grupuri.in","r",stdin);
    freopen("grupuri.out","w",stdout);
    long long n,k,st,dr,mij,i,s=0,rez;
    scanf("%lld %lld",&k,&n);
    for(i=1;i<=n;i++)
    {
        scanf("%lld",&v[i]);
        s+=v[i];
    }
    st=1;
    dr=s/k;
    while(st<=dr)
    {
        mij=(st+dr)/2;
        s=0;
        i=1;
        while(s<mij*k && i<=n)
        {
            if(v[i]<mij)
            {
                s+=v[i];
            }
            else
            {
                s+=mij;
            }
        }
        if(s>=mij*k)
        {
            rez=mij;
            st=mij+1;
        }
        else
        {
            dr=mij-1;
        }
    }
    printf("%lld",rez);

    return 0;
}