void select_activitati(int x[], int* nr_activitati){
	//se selecteaza activitatile conform strategiei greedy
	//x[i] contine numere 0:n-1
	//x[i] = k, inseamna ca am selectat activitatea k
	//nr_activitati se modifica
	int minstart =999;
	for(int i=0; i<n; i++)
        if(activitati[i].s<minstart)
    {
        minstart= activitati[i].s;
        x[0]=i;
    }
	int gasit;
	int pos=0;
	int min;
	int can_continue=1;
	*nr_activitati = 1;
	while(can_continue)
    {
        min=999;
        gasit=-1;
        for(int i=0; i<n; i++)
        {
            if((activitati[i].s <= min) && (activitati[i].s >=activitati[x[pos]].f))
                {
                    min=activitati[i].s;
                    gasit=i;
                }
        }
        if(gasit==-1)
            can_continue=0;
        else
        {
            pos++;
            x[pos]=gasit;
            (*nr_activitati)++;
        }
    }

}