#include <fstream>

using namespace std;

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

int n, k, grupe;
int v[100000];
long long sum;

int main()
{
    in >> k >> n;
    for(int i = 0; i < n; i ++){
        in >> v[i];
        sum += v[i];
    }
    for(int i = n - 1; i >= 0; i --){
        int adaos = 0;
        bool stop = 0;
        out << "GRUPA " << n - i << endl;
        for(int j = 0; j < k && stop == 0; j ++){
            while(!v[n - j - adaos - 1] && n - j - adaos - 1 >= 0){
                adaos ++;
            }
            v[n - j - adaos - 1] --;
            out << n - j - adaos - 1 << " ";
            if(n - j - adaos - 1 < 0)
                stop = 1;
        }
        out << endl;
        if(stop == 0)
            grupe ++;
        else
            break;
    }
    out << grupe;
    return 0;
}


/// 1: sum / k
/// 2: foloseste de la maxim catre minim pentru grupari