#include <fstream>
#include <algorithm>
#define NM 1000005

using namespace std;

ifstream fin("grupuri.in");
ofstream fout("grupuri.out");

int n, k, i, s;
int v[NM], nr, sol;

int main()
{
    fin >> k >> n;
    for (i=1; i<=n; i++)
      fin >> v[i];
    if (k==n)
      fout << v[1];
    else
    {
        while (n-nr>=k)
        {
            sol++;
            for (i=n; i>=n-k+1; i--)
            {
                if (v[i]==1)
                  nr++;
                v[i]--;
            }
            sort(v+1, v+n+1);
        }
        fout << sol << " ";
    }
    fin.close();
    fout.close();
    return 0;
}